LIBRARY OF CONGRESS. 






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UNITED STATES OF AMERICA. 



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A TREATISE OX 



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INTRODUCING 

A NEW SYSTEM TO COMPLETE COMBUSTION. 



ALSO A COMPENDIUM OF 

MISCELLANEOUS VALUABLE INFORMATION. 

DEVOTED TO 

MANUFACTURERS, STEAM-USERS, ENGINEERS, 
MECHANICS, ETC. 



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V, 




PUBLISHED BY THE 

NATIONAL ELECTRIC FURNACE CO. 
ST. LOUIS, MO. 

1887. 




COPYEIGHT. 

Entered, according to Act of Congress, in the year 1887, by 
Geo. Hasecoster, ^-? / 
In the Office of the Librarian of Congress at Washington, D. C. 



ALL RIGHTS RESERVED. 



Copies of this Book will be sent by mail, postpaid, to all parts 
of the U. S. A. on receipt of price. 



£-330*7 



PREFACE. 



This little volume, introducing a new system of 
combustion, will be found to embrace a number of 
instructive truths pertaining to the science of com- 
bustion. These truths have been collated from many 
reliable sources with great care. The writer having 
for over twenty-five years had theoretical and prac- 
tical experience as a steam user and engineer, deemed 
the information herein contained valuable enough to 
be presented to others interested in the same subject, 
who, although in proper state for receiving these 
truths, remain in total ignorance of their existence, 
and have no means of knowing them except through 
some such effort as this. For the benefit of all 
such, certainly, not for the writer's own emolument 
except so far as happiness may be derived from the 
consciousness of having tried to be of use to others, 
the following pages have been transmitted to publi- 
cation. 

St. Louis, November, 1886. 

Geo. Hasecoster. 



TABLE OF CONTENTS. 



PAGE 

The Science op Combustion 1 

Catechism of Combustion and Steam 10 

What is combustion? An elementary substance? Fire? 10 

. What is hydrogen? Carbon? Oxygen? 11 

What is the composition of air? Nitrogen? 12 

What effect has combustion upon air? What are the com- 
ponents of coal? 13 

What is flame? The gas which escapes from the coal? 14 

What is smoke? 15 

What is steam? What are the chemical components of 
water? What is the volume of steam compared to the 
volume of water from which it was made? What is dry 

steam? Superheated steam? Wet steam? 16 

What is the sensible heat of steam at atmospheric pressure? 
What is latent heat? The most economical steam 

pressure? 17 

What are the properties of saturated steam? 18 

What is the power of boilers? 19 

Ordinary Steam-boiler Furnaces 20 

Disadvantages 21 

Experiments made to remedy them 22 

Smoke-preventing 23 

Enormous waste 24 

Reformation 25 

The "National Electric Furnace." 

Aims and Advantages 26 

Description 27 

Operation '. 33 

Directions 35 

Waste of heat avoided and exhaust steam utilized 36 

Cost of fan outweighed 38 

Backpressure diminished. — Advantage of the National 
Electric Furnace of other furnaces with artificial forced 

draught 39 

Other advantages. — The National Electric Furnace can be 
Avorked like other forced draught furnaces, or even like 

an ordinary steam boiler furnace, as occasion requires 40 
Plant may be varied.— Can be adapted to boilers of any 

approved construction 41 

Blowing-engine and mixing apparatus combined 42 

The National Electric Furnace may be applied to a battery 

of boilers 44 

Table of "National Electric Furnace" 45 

Table of Ordinary good furnace 46 

National Electric Furnace patented 47 



PAGE 

artificially forced combustion 48 

Useful Information 55 

Table of American Coal.— Furnace Efficiency 56 

Temperature of fire 57 

Table to determine temperature t>y fusion of metals, etc.— 
Table of relative value of non-conductors.— Firing of 

sawdust and shavings 58 

Amount of coal burned by ocean steamships 60 

Boiler explosion 61 

Table of proportions, heating surface, and horse -power of 

boilers fitted with six inch flues 63 

Table of proportions, heating surface, and horse-power of 

boilers fitted with four inch tubes 64 

The prevention of scale in steam boilers 65 

Instructions to engineers 71 

Employ qualified engineers 74 

New boilers and engines. 75 

Practical remarks on combustion and firing of steam boilers. 76 

Coal Tar Product '. .- 78 

Valuable information for business men 79 

Table of compound interest on $1 for 100 years.— Greatest 
known depth of the ocean.— First steamboat and loco- 
motive in the United States.— Long measure table. — 

Lightning rods 80 

Scraps of information 81 

Table of capacity of cisterns for each 10 in. in depth 82 

Table of velocity and force of the wind 83 

Distinguished American inventors 84 

The great wonders of America.— Height of principal monu- 
ments and towers in the world 85 

Highest and greatest mountains in the world 86 

Longest and greatest rivers in the world 88 

Number of miles by water from New York to different 

places.— Years of age which various animals attain 89 

Boilers of Various Types, Boiler Attachments, etc. 

Babcock and Wilcox Boiler 92 

Root's New Safety Boiler 94 

Harrison Boiler 96 

The Aetna Grate 98 

Priming in steam-boiler 99 

Dry Steam Separator 101 

Albany Steam Trap 102 

L. and N. Automatic Water Gauge 105 

What is Conduction of Heat? '. 106 

Atmospheric Pressure.— Pump. — The Sun 107 

What is Water?— Why is the Sea salty? 108 

What is the Depth of the Sea?— What Proportion of the Earth's 
Surface is covered with Water?— How do the Waters of the 

• Ocean become heated? 109 

The Coal Industry 110 

The Fuel Use of the City of London Ill 

Useful Notes on Specific Heat for Engineers and Firemen 112 

Open Heaters, Grease in Boilers 113 

Earthquakes 115 

Conclusion 116 




National Electric Furnace. 

The object of the improvement herewith illustrated is to provide 
a furnace for steam boilers of any approved construction, in which 
furnace a complete combustion of the fuel is accomplished by in- 
troducing a mixture of steam, (exhaust steam), hot air, and gases 
into the fuel. The above engraving represents a fire tube, or flue 
boiler, mounted in brickwork. This furnace takes the combustible 
gases from the hot air chamber, and, after adding steam and air, 
forces them into the combustion chamber, where they not only 
serve to support combustion, but themselves constitute a new fuel 
(water gas). By these means the great waste of fuel can be 
avoided, and a greater volume of water evaporated with less fuel. 



For further information address 

National Electric Furnace Co., St. Louis. 



Artificially Forced Combustion. 




Introduction. 

The Science of combustion and the enormous waste of fuel, in 
small fires, as in domestic operations, in stoves, and furnaces, 
while imperfectly understood even by most men of science, is 
scarcely thought of by the great mass of people. This little volume 
will enable those, who are entirely unacquainted with the science 
of combustion to understand the same and the elements that take 
part in it. 

It will give answers to the following questions. What is coal?— 
What is fire?— What is flame?— What is heat?— What is carbon?— 
What is the composition of air?— What is oxygen?— What is hy- 
drogen?— What is gas which escapes from the coal?— What is ni- 
trogen?— What is smoke?— What is water?— What is steam?— 

It will show that the nature of combustion is nothing more than 
an energetic chemical combination, or, in other words, that it is 
the mutual neutralization of opposing electricities, as will herein- 
after be explained. It will also serve to introduce a new system 
of combustion in furnaces for steam boilers and for other pur- 
poses. G. H. 



The Science of Combustion. 



The science of combustion is in itself simple, but 
to those who are entirely unacquainted with it, it 
appears mysterious. Since, however, there are a 
great many, to whom this science really is a mys- 
tery, we have deemed it necessary to premise this 
small treatise in order to enable a better under- 
standing of the advantages of the "National Electric 
Furnace." This treatise has been adapted from the 
second part of a work, entitled "Library of Popular 
Sciences," by one A. Bernstein, a German writer 
on natural science. The work named was published 
by Chr. Schmidt of New York, and the passage re- 
ferred to reads mainly as follows : 

"Chemical elementary substances have a peculiar 
tendency to unite, and this tendency is strongest 
between substances that are naturally most dissim- 
ilar. But we must not suppose that two substances 
will always unite immediately on being brought into 
contact, for certain circumstances must generally 
meet in order to effect, support, and hasten the 
uniting. 

Oxygen and coal united form carbonic acid, but 
in order to effect the union of oxygen and coal the 
latter must be ignited, that is to say, the union of 
oxygen and coal is effected by the application of a 
certain degree of heat to the latter. This is also 



Z THE SCIENCE OF COMBUSTION. 

the case with other substances. Sulphur may be 
left in oxygen for days without uniting with it, but 
as soon as a small portion c£ the former is ignited, 
the union will be effected and produce such heat as 
will be needed to ignite the rest of the sulphur and 
thus make the union progress. 

It is quite important to explain this as clearly as 
possible, for it will enable us to understand a great 
man}- phenomena which are daily taking place be- 
fore our eyes. 

How is it that wood when brought into contact 
with live coal, will ignite and change into coal? The 
reason is that live coal impart to wood a high de- 
gree of heat, when brought into contact with it. 
Since wood itself, however, consists to a great ex- 
tent of carbon, the heat from the live coal causes 
the carbon of the wood to unite with the ox} T gen of 
the air, and thus the particles of wood in direct 
contact with the live coal are ignited. Fresh air is 
therefore absolutely necessary for the progress of 
the union, since it can only continue as long as it is 
supplied with fresh oxygen. The supply of ox}-gen 
being cut off, the chemical union of oxygen and 
carbon will cease, the fire will go out. 

Every child, therefore, already knows that fire in 
a stove in order to burn well must have a good 
draught ; the hot air having been robbed of its oxy- 
gen, must leave the stove by way of the flue above, 
and fresh air containing oxygen, must enter the 
stove from below, so that the oxygen may contin- 
ually unite with the heated coal and the fire burn on. 
Indeed, no fresh air, and hence no new oxygen be- 
ing allowed to enter the stove, the fire will go out, 
for fire only originates through the oxygen of the 
air entering into a state of chemical union with the 
carbon of the wood. If an apparatus could be con- 



THE SCIENCE OF COMBUSTION. 6 

structed to create fresh oxygen within the stove, 
this would do away with the draught; for, while 
there is oxygen within the stove,' the fire will burn, 
or, in the language of chemists, the chemical union 
of oxygen and carbon will take place. 

Hence it is quite natural that fires burn best in 
stoves with a good draught — that is to say, stoves, 
through which a strong current of air is continually 
passing — because a large quantity of oxygen passes 
from the air info the heated fuel and unites with it 
chemically. We also blow into a fire to make it 
burn brighter, that is, by blowing we drive a greater 
volume of air into the fire and thereby bring more 
oxygen into contact with the heated wood. The 
blacksmith makes use of his bellows to force a great 
volume of air into the fuel and thereby causes a 
rapid and energetical chemical union of oxygen and 
carbon resulting in fire, since fire itself is but a phe- 
nomenon occurring whenever oxygen is rapidly and 
energetically united with carbon or other substances. 

So we find it to be quite true what chemistry 
teaches about combustion, viz., that combustion is 
nothing but a chemical process, and that fire is only 
the phenomenon resulting from such process, and we 
also find that chemistry is practised unconsciously 
by almost everybody, for as often as we fight a 
lamp or kindle a fire, we do but effect a state or 
condition in which certain substances may unite 
with the oxygen of the air. 

A light will be extinguished by .being deprived 
of the oxygen of the air. Place a small end of 
a taper on the table, light it, and cover it with 
a tumbler. You will soon see the flame grow darker, 
until finally the light will go out. Why is this ? The 
oxygen contained within the tumbler has been con- 
sumed, and hence the chemical union, called com- 



4 THE SCIENCE OF COMBUSTION. 

bustion, ceases. So you see, that combustion can 
only continue while the combustible is uniting with 
the oxygen of the air. If means could be found to 
extract the oxygen fjom large volumes of air, we 
should be able to extinguish the largest conflagration 
in an instant simply by depriving the fire of the 
oxygen. 

The flame of a common light also may teach us a 
great deal. The edge of the flame, coming closely 
into contact with the oxygen of the air, is hot and 
bright, while the centre, coming very little into con- 
tact with the oxygen, is neither as bright nor as hot. 
Hold a chip of wood directly into the flame, and 
you will notice, that the chip will not catch fire first 
in the centre of the flame, but on the edges. With 
a little dexterity the chip can be taken out, before 
it catches fire, and then you will notice that only 
the edges of the flame have charred it, while the 
centre of the flame hardly singed it. 

This teaches us that the faster and readier a com- 
bustible unites with oxygen, the greater a degree of 
heat will be originated, and the slower and more 
reluctant a substance unites with oxygen, the lower 
a degree of heat will be originated. — And now we 
can also easily understand why it is, that stoves, in 
which the fuel is consumed slowly, will radiate less 
heat, while stoves, in which the fuel is consumed 
more rapidly, will also radiate more heat. The 
former have not sufficient draught, the quantity of 
oxygen coming into contact with the fuel is therefore 
not sufficient and so the flame not hot enough. In 
stoves with a good draught, the quantity of oxygen 
coming into contact with the fuel is sufficient, the 
flame is hotter, heats the stove more rapidly and to 
a higher degree, so that the stove radiates more heat. 

It is also quite important that a sufficient quan- 



THE SCIENCE OF COMBUSTION. 5 

tity of oxygen be admitted to the flame for the 
reason that it will cause a great many particles of 
the fuel to be consumed, which would otherwise 
pass away unconsumed. Every cook knows that, 
whenever the fire in the range will not burn, a great 
volume of smoke is formed, but after having been 
blown into, the flame will leap up and the smoke 
disappear. Smoke, however, is hardly anything 
else but fine carbon, which rises with the hot air 
from the fire. By blowing into the fire, we know, 
a greater quantity of oxygen is imparted to it, and 
its heat is increased to such an extent, that the fine 
particles of carbon contained in the smoke will 
unite with the oxygen and give a beautiful hot flame. 
By withdrawing the oxygen, however, the fine par- 
ticles of carbon in the smoke and, therefore, a val- 
uable part of the fuel, pass on, partly settling in 
the chimney, partly flying out into the open air and 
settling on surrounding surfaces in the form of soot. 
— A common coal-oil lamp will afford an excellent 
experiment to prove this. Take off the chimney, 
and the light will flicker, form smoke, and grow 
dim ; put the chimney on again, and the light will 
instantly burn with a bright, pure, and white flame. 
How can this be accounted for? Why, the chimney 
being open above and below, causes a strong cur- 
rent of air. The hot air constantly leaves by the 
opening above, and fresh air as continually enters 
from below. This current of air constantly supplies 
the flame with oxygen, and thus a sufficient degree 
of heat is originated to consume even the soot. As 
soon, however, as the chimney is taken off, the 
current of air ceases, the quantity of oxygen sup- 
plied by the surrounding air is insufficient for a 
good combustion, and so a part of the combustible 
is lost in the form of soot. 



6 THE SCIENCE OF COMBUSTION. 

Since combustion is nothing but a chemical union 
effected chiefly between carbon and oxygen, and 
fire is but a phenomenon attending this union, what 
may be the product of this union, or what originates 
from it? The product of this union is chiefly car- 
bonic acid, a substance also occurring free as a gas 
in. the atmosphere, to the extent of 1 volume to 
2500 of air, and also in combination with a variety 
of substances. It is often called fixed air or choke 
damp, and being poisonous can not be inhaled with- 
out danger, as it not only furnishes no oxygen for 
purifying the blood, but it adds additional poison to 
it. As combustion can not be produced in common 
air without consuming oxygen, and giving out in its 
place carbonic acid, an open fire in a close room 
must render the air impure. If a lighted taper be 
placed in a closed jar containing common air, the 
oxygen will soon be burned up, its place will be 
supplied with carbonic acid and vapor, and the light 
of the taper will be extinguished. If a living an- 
imal, a mouse, for example, be now placed in the 
jar, and especially at the lower part of it, the an- 
imal will almost immediately go into convulsions, 
and die in two or three minutes. 

As pure charcoal consists almost entirely of car- 
bon, the burning of charcoal produces a large quan- 
tity of carbonic acid ; and every year cases occur 
of individuals having lost their lives by entering 
close rooms in which charcoal was burning.' As 
this gas is much heavier than common air, it may 
occupy the lower portion of a room near the floor, 
while the air above may be nearly free from its in- 
fluence. Persons have also lost their lives by de- 
scending into deep pits, wells, and mines, which 
contained carbonic acid. Before venturing into 
such places the precaution should be used of let- 



THE SCIENCE OF COMBUSTION. 7 

ting down a lighted candle ; if the light be extin- 
guished, or burn feebly, carbonic acid may be 
known to exist there. When discovered it may 
often be absorbed by quick lime, if it can not be 
drawn off or dissipated by ventilation. 

We have adduced these remarks on carbonic acid 
in order to show that really every stove is a chem- 
ical factory producing carbonic acid, and because 
we think it most important that everybody should 
be instructed in regard to the dangers of the same, 
too many sad results constantly occurring from 
ignorance or disregard of them. For this purpose, 
we also add, that in dubious cases, whenever the 
presence of carbonic acid in a room is but supposed, 
we mu^ not judge according to the higher strata 
of air in the room, but explore the lower in order 
to insure against accidents. 

In speaking of the elementary substances taking 
part in combustion we have hitherto mentioned two, 
oxygen and carbon, the former of which is supplied 
by atmospheric air, while the latter exists in the fuel. 
But fuel, especially coal, the fuel most in use, does 
not consist of pure carbon alone, but also contains 
hydrogen, and, therefore, we can not afford to pass 
this substance by unnoticed. This substance, which 
is also a gas, may seem to be unknown to most 
people, but in reality everybody is well acquainted 
with it, since it strikes our eyes hundreds of times in 
a single day. The gas of the lamps in our streets 
consists chiefly of hydrogen mixed with a little car- 
bon. The burner of a gaspipe being opened, a gas 
or air will stream forth, which is invisible to the 
eye, but as soon as a lighted match is held above 
the burner, the air or gas around the match will 
ignite, and the flame will go downward to the open- 
ing of the burner and proceed to burn there, while 
2 



8 THE SCIENCE OF COMBUSTION. 

the gas streams forth. If the lighted match be held 
a little distance above the burner, the flame will 
seem to drop from the match to the burner, but a 
little reflection will readily bring us to the conclusion 
that this is a misconception. 

We have presented this example of common gas 
in order to show that hydrogen is really not a kind 
of matter entirely unknown to us. Common gas, 
however, does not consist of pure hydrogen alone, 
and we will, therefore, seek to become acquainted 
with the latter. 

Hydrogen, so called from the Greek word hydor, 
water, forms two thirds of the bulk of water. For 
all the water of wells, rivers, lakes, and seas is not 
an elementary substance, but consists of twx> kinds 
of gases chemically united, one being hydrogen and 
the other oxygen, both of which can be produced 
out of water. Indeed, if ever means should be 
found, which would enable man to produce both of 
these gases out of water at a small expense, human- 
ity would have taken a great step forward, for we 
should then be able to procure the fuel for kitchen, 
shop,* and factory from the same water, which has 
hitherto been thought to constitute the very reverse 
of fire. 

Fire is extinguished by water thrown upon it, 
because the water cools the burning objects and 
robs them of the heat necessary for combustion. 
The light of a lamp is extinguished by being blown 
into, because the cold air forced upon the light cools 
it and so prevents the combustion from continuing. 
In both cases, we see that combustion ceases, as 
soon as it is robbed of the temperature necessary 
for its sustenance. If the temperature of the fire 
be high enough and the amount of water thrown 
upon it small in proportion, the water will not only 



THE SCIENCE OF COMBUSTION. 9 

be ineffectual in extinguishing the fire, but will 
even further and support it. It can easily be no- 
ticed that, when a stream of water is thrown into a 
great conflagration, the vast heat changes the water 
into steam even before it reaches the objects on fire. 
If, however, the heat reach a still higher degree, 
the steam will be expanded to such an extent, that 
the chemical union of the two elementary substances 
of water is dissolved, and in place of water two sep- 
arate gases, hydrogen and oxygen, will reach the 
flames and nourish the fire instead of extinguishing 
it. That combustion thus may be furthered by 
water, is known practically, if not theoretically, to 
every blacksmith, who sprinkles his coal with water 
before working his bellows. The great heat pro- 
duced by the combustion of the coal, when a strong 
current of air (and hence of oxygen) is forced into 
them by the action of the bellows, suffices to de- 
compose water into its elementary substances, which 
are genuine supporters of combustion. ' ' 

The manner in which the chemical union called 
combustion takes place having thus been illustrated, 
we will now proceed to treat more fully of the ele- 
ments themselves that take part in combustion. We 
have adopted the style of a catechism, because we 
believe the method of questions and answers best 
suited for the purpose of fixing facts on the mind 
of the average reader. We have also added as many 
questions and answers on the properties of steam, 
as we deemed necessary for our purpose. 



CATECHISM 

OF 

COMBUSTION AND STEAM. 



What is combustion^ 
Combustion* is the term usually applied to the 
process of burning, which consists in the chemical 
union of several elementary substances. 

What is meant by an elementary substance^ 
An elementary substance is one of those sub- 
stances in which chemistry is unable to discover 
more than one constituent. 

What is combustion commonly called^ 
It is called fire. It imparts heat, which has the 
effect of expanding both fluids and solids. It can 

* Combustion is nothing more than an energetic chemical union, 
or, in other words, it is the mutual neutralization of opposing 
electricities. When coal is brought to a high temperature, it ac- 
quires a strong affinity for oxygen, and a combination with oxygen 
.will produce more and has sufficient heat to maintain the original 
temperature; so that part of the heat is rendered applicable to 
other purposes. 

We have said that combustion is the mutual neutralization of 
opposing electricities ; what th§n is electricity ? It is a power in 
nature, evolved in any disturbance of molecular equilibrium 
whether from a chemical, physical, or mechanical cause ; it is a 
property of force which resides in all matter, from the metal to the 
gases, and which constantly seeks to establish an equilibrium.— 
How does the equilibrium of electricity become disturbed ? By 
changes in the condition of matter. As electricity resides in all 
substances and is perhaps an essential ingredient in their con- 
dition, so every change in the state of matter disturbs the elec- 
trical equilibrium, and the force exerted by electricity to resume 
its balance in the scale of nature is in proportion to the degree of 
disturbance. 



CATECHISM OF COMBUSTION AND STEAM. 11 

not exist without the presence of combustible ma- 
terials. It has a tendency to diffuse in every direc- 
tion. It can not exist without oxygen or atmos- 
pheric air. 

What elements, or elementary substances, take part in 
the maintenance of a fire? 

Hydrogen, carbon, and oxygen. Hydrogen and 
carbon exist in the fuel, and oxygen is supplied by 
the air. 

What is hydrogen? 

Hydrogen is an elementary substance, which ex- 
ists in the form of a permanent, colorless, and 
inodorous gas. One of its most striking peculiar- 
ities is its specific gravity, it being the lightest of 
all known bodies, fourteen and a half times lighter 
than common air. 

Where does hydrogen chiefly exist? 

In water, where it exists in combination with 
oxygen, eleven parts of hydrogen and eighty- nine 
of oxygen forming water. 

What is carbon? 

It is also one of the elementary bodies and is very 
abundant throughout nature. It abounds mostly in 
vegetable substances, but is also contained in min- 
eral bodies and in minerals. The form in which it 
is most familiar to us is that of charcoal, which is 
carbon almost pure. 

What is oxygen? 

Oxygen, a colorless, inodorous, tasteless gas, is 
the most abundant and the most widely distributed 
of all elements. Mixed with .nitrogen it constitutes 



12 CATECHISM OF COMBUSTION AND STEAM. 

about a fifth of the bulk, and considerably more 
than a fifth of the weight of the atmosphere. In 
combination with hydrogen, it forms eight ninths 
of all the water on the globe. Owing to the intensity 
with which it combines with a great many element- 
ary substances, this gas has the power of supporting 
combustion in an eminent degree. 

What is the composition of the air in its natural state? 

It consists of oxygen, nitrogen and carbonic acid 
gas in the proportions of oxygen 20 volumes, nitro- 
gen 79 volumes, and carbonic acid 1 volume. 

What is nitrogen? 

Nitrogen, a colorless, tasteless, inodorous, per- 
manent gas, which in its appearance in no way 
differs from the atmospheric air, of which it is the 
main ingredient, is also one of the most widely 
diffused elementary substances. It forms about 
four fifths by bulk of the atmosphere. 

Will nitrogen burn ? 

It will not burn, neither will it support combustion 
or respiration. A lighted taper introduced into it 
is immediately extinguished, and animals placed 
within it soon die. 

Why is the oxygen of the air mixed so largely zoith 
nitrogen? 

Because oxygen in any greater proportion than 
that in which it is found in the atmosphere, would be 
too exciting to the animal system. Johnston, the 
renowned English chemist (b. 1796, d. 1855), says 
"As a candle burns in oxygen gas with much 
greater brilliancy and rapidity than in common air, 
so animals breathe in it with an increase of pleasure ; 



CATECHISM OF COMBUSTION AND STEAM. 13 

but it excites them, quickens their circulation, 
throws them into a state of fever, and finally kills 
them by excess of excitement. They live too rapidly 
in pure oxygen gas, and burn away in it like the 
fast-flaring candle." 

What effect has combustion upon the composition of 
the air? 

In combustion the oxygen of the air is absorbed. 
It has been found that in burning 10 lbs. of coal, 
the oxygen contained in 1500 cu. ft. of air was al- 
together absorbed, which will make 150 cu. ft. of 
air to every pound of coal that is consumed. 

What fuel is most in use for general purposes'* 
The fuel most in use for general purposes is coal. 

What are the chemical components of coal 1 ? 

For all ordinary purposes, it is sufficient to say 
that coal consists of carbon and hydrogen, but 
mainly of carbon. 

Why does poking afire cause it to burn more brightly'? 

Because it opens avenues through which the air 
may enter to supply oxygen. 

Why do "blowers" improve the draught of air through 
a fire'? 

Because by obstructing the passage of the current 
of air above the fire, they cause additional air to 
pass through it, and a greater amount of oxygen is, 
therefore, carried to the coal. 

What makes combustion apparent to the eye? 

Combustion is made apparent to the eye by the 
flame and smoke attending it. 



14 CATECHISM OF COMBUSTION AND STEAM. 

What is flamed 

It is the burning of gas, which takes place only 
when the temperature is very high. 

Does gas burn at all at a low temperature? 

It does not ; when we throw fresh coal upon the 
fire, we may hear the gas escape from the coal with- 
out taking fire. 

Why is this? 

The fire being slow, the temperature is not high 
enough to ignite the gas. 

What is the gas which escapes from the coal? 

Carburetted hydrogen, a gaseous compound of 
carbon and hydrogen. 

Why will the hydrogen burst into flame, when the coal 
have become thoroughly heated? 

Because the carbon of the coal and the oxygen 
of the air have begun to unite, and have greatly 
increased the heat, and have produced a rapid 
combustion so nearly allied to flame, that it ignites 
the hydrogen. 

What temperature is required to produce flame? 

That depends upon the nature of the combustible 
you desire to burn. Finely divided phosphorus and 
phosphorated hydrogen will take fire at a temper- 
ature of 60 or 70 degrees, solid phosphorus at 140 
degrees, sulphur at 500 degrees, carbonic oxide at 
1000 degrees (red heat), coal gas, ether, turpentine, 
alcohol, tallow, and wood at about 2000 degrees 
(incipient white heat). When once inflamed, they 
will continue to burn and will maintain a very high 
temperature. 



CATECHISM OF COMBUSTION AND STEAM. 15 

What is smoke? 

Smoke consists of small particles of carbon, of 
hydrogen gas, and of other volatile matters, which 
are driven off by the heat and carried up the 
chimney. 

What do small particles of carbon form, when separated 
from the other constituents of smoke? 

They are called soot. 

Why do fresh coal when thrown into the fire, increase 
the quantity of the smoke? 

Because they contain volatile matters, which are 
easily driven off, and because they also reduce the 
heat momentarily, so that the matter first escaping 
can not be consumed. 

Are all the constituents of smoke incombustible? 

Not at all ; under proper management the major- 
ity of them might be utilized for combustion. 

Is it not a waste of fuel to allow these to escape? 

It is ; the smoke from the numerous chimneys in 
our large cities daily covers the house tops and 
streets with soot and coaldust and fills the atmos- 
phere with gases invisible to the eye. This immense 
waste in the city of St. Louis alone amounts to 
thousands of tons of coal annually. We are quite 
convinced that this waste might be done away with 
almost entirely by" better management. We are, 
furthermore, fully convinced that the "National 
Electric Furnace" will not only do away with this 
waste, but will also offer greater advantages for the 
production of steam than any other known boiler 
furnace. 



16 CATECHISM OF COMBUSTION AND STEAM. 

II. 

What is steam? 
Steam is water in the gaseous form. 

What are tlie chemical components of water? 

Chemists tell us that water is the result of two 
gases, known as hydrogen and oxygen, two volumes 
of hydrogen to one of oxygen, or eight parts by 
weight of oxygen to one of hydrogen. 

What is the volume of steam compared to the volume of 
water from which it was made? 

The volume of steam at 15 lbs. pressure to the 
square inch or atmospheric pressure is 1700 times 
greater than that of any given quantity of water 
from which it may be derived. If 520 cu. ft. of 
water be evaporated, the volume of steam at atmos- 
pheric pressure would be 884000 cu. ft. If analyzed, 
there would be two volumes, about 589333 cu. ft., 
of hydrogen to one volume, about 294666 cu. ft., 
of oxygen. If about two thirds of this volume were 
utilized or converted into a mixture of fuel, there 
would be 196444 cu. ft. of oxygen to support com- 
bustion, and 392888 cu. ft. of hydrogen would be 
made to burn. 

What is meant by dry steam? 
Dry steam is that which is devoid of water held 
in suspension. 

What is meant by superheated steam? 
Superheated steam is that which is heated above 
the temperature due to its pressure. 

What is meant by wet steam? 
Wet steam is that which holds water in suspension. 



CATECHISM OF COMBUSTION AND STEAM. 



17 



What is the sensible heat of steam at atmospheric pressure? 
The sensible heat of steam at atmospheric press- 
ure is 212 degrees, that is, it takes 180 degrees of 
heat to raise water at 32 degrees to the boiling 
point, and 32 ° + 180 ° = 212 °. 

What is meant by latent heat? 
By latent heat is meant the heat existing in bodies 
which is not discoverable by the touch or by the 
thermometer, but which manifests its existence by 
producing a change of state. Heat is absorbed in 
the liquefaction of ice, and in the vaporization of 
water, yet the temperature does not rise during 
either process, and the heat absorbed is therefore 
said to become latent. The latent heat, in point of 
fact, is not uniform at all temperatures; neither is 
the total amount of heat the same at all temperatures. 
That the total heat in steam increases somewhat 
with the pressure, and that the latent heat dimin- 
ishes somewhat with the pressure, will be made 
obvious by the following numbers : 



PRESSURE 


TEMPERATURE 


TOTAL HEAT 


LATENT HEAT 


lbs. 


Degrees. 


Degrees. 


Degrees. 


15 


213.1 


1178.9 


965.8 


50 


281.0. 


1199.6 


918.6 


100 


327.8 


1213.9 


886.1 



If, then, steam of 100 lbs. be expanded down to 
steam of 15 lbs., it will have 35 degrees of heat 
over that which is required for the maintenance of 
the vaporous state, or, in other words, it will be 
surcharged with heat. 

What is the most economical steam pressure? 
The most economical steam pressure is from eighty 
to ninety pounds to the square inch on the piston 
of any high pressure steam engine. 



18 



CATECHISM OF COMBUSTION AND STEAM. 



What can you tell about the properties of saturated steam ? 

The following table gives the value of all proper- 
ties of saturated steam required in calculations con- 
nected with steam-boilers. 



Properties of Saturated Steam. 



Pressure 




Volume 




B2-o 






£ § 






&i 


n - u 








u 

ii 




be 




sg 


5 


aS 






o 


s2 


-3 a 


— be 


o 


u 

g 


CO 


® 


sls§ 






• H 


O 


5B 


-* 


~ tc-i-s 














In heat units 





15 


212.0 


1642 


26.36 


965.2 


1146.1 


5 


20 


228.0 


1229 


19.72 


952.8 


1150.9 


10 


25 


240.1 


996 


15.99 


945.3 


1154.6 


15 


30 


250.4 


838 


13.46 


937.9 


1157.8 


20 


35 


259.3 


726 


11.65 


931.6 


1160.5 


25 


40 


267.3 


640 


10.27 


926.0 


1162.9 


30 


45 


274.4 


572 


9.18 


920.9 


1165.1 


35 


50 


281.0 


518 


8.31 


916.3 


1167.1 


10 


55 


2S7.1 


474 


7.61 


912.0 


1169.0 


45 


60 


292.7 


437 


7.01 


908.0 


1170.7 


50 


65 


298.0 


405 


6.49 


904.2 


1172.3 


55 


70 


302.9 


378 


6.07 


900.8 


1173.8 


60 


75 


307.5 


353 


5.68 


897.5 


1175.2 


65 


80 


312.0 


333 


5.35 


894.3 


1176.5 


70 


85 


316.1 


314 


5.05 


891.4 


1177.9 


75 


90 


320.2 


298 


4.79 


888.5 


1179.1 


SO 


95 


324.1 


283 


4.55 


885.8 


1180.3 


85 


100 


327.9 


270 


4.33 


883.1 


1181.4 


90 


105 


331.3 


257 


4.14 


880.7 


1182.4 


95 


110 


334.6 


247 


3.97 


87S.3 


1183.5 


100 


115 


338.0 


237 


3.80 


875.9 


1184.5 


110 


125 


344.2 


219 


3.51 


871.5 


1186.4 


120 


135 


350.1 


203 


3.27 


867.4 


1188.2 


130 


145 


355.6 


190 


3.06 


863.5 


1189.9 


140 


155 


361.0 


179 


2.87 


859.7 


1191.5 


150 


165 


366.0 


169 


2.71 


856.2 


1192.9 


160 


175 


370.S 


159 


2.56 


852.9 


1194.4 


170 


185 


375.3 


151 


2.43 


849.6 


1195.S 


180 


195 


379.7 


144 


2.31 


846.5 


1197.2 



CATECHISM OF COMBUSTION AND STEAM. 19 

What is the power of boilers? 

Regarding the power of boilers, it may be stated 
that a boiler 30 ft. long and 3 ft. in diameter will 
afford 30 X 3 X 3. 14 -f- 2 = 141. 30 sq. ft. of heating 
surface, or steam for 14 horse-power. The term 
horse-power has been applied to boilers, and has 
been used so long in connection with them, that it 
will probably "stick," so we must make the best 
of it. This can only be done by assuming some 
standard evaporative power for a measure and rating 
boilers accordingly. Such a standard was recom- 
mended by the judges at the Centennial in 1876. 
This standard is : The evaporation of thirty pounds 
oficater per hour from feedivater, having a temper- 
ature of 100° Fahr., into steam, having a pressure 
of seventy pounds per square inch above the atmos- 
phere, is equal to one horse-poiver. 

If a boiler, fitted with 1 8 — 6 in. flues. 60 in. in diameter, 

18 ft. long, contain 697 sq. ft. heating surface, why is 

it rated 58.1 horse-power? 

Because it requires the above boiler to evaporate 
the necessary amount of water to furnish steam for 
the above power in an ordinary good steam-engine. 

Why can not the size of boilers and the space of furnaces 
be reduced and more water be evaporated per hour? 

It can. The "National Electric Furnace' ' will 
accomplish it. The improvement set forth in this 
furnace, its merits, its working, and the advantages 
of same over any other furnace ever invented, of 
which we have any knowledge, will be explained 
subsequently. We shall now refer to the ordinary 
steam-boiler furnaces, their disadvantages, and the 
experiments made to remedy the latter. 



Ordinary Steam-boiler Furnaces. 



For years great progress has been made in the 
improvement" of boilers and engines, while the con- 
struction of furnaces for setting boilers has been 
left to the judgment of any mason, each setting 
his own way. But we are pleased to see a change 
taking place and steam-users paying closer attention 
to the details of their boiler setting, and looking for 
devices by which the disadvantages and great waste 
accompanying ordinary steam-boiler furnaces might 
be avoided. But what are the disadvantages of the 
ordinary steam-boiler furnace, and how is the great 
waste going on? That is just what we shall try to 
explain in the following. 

In an ordinary steam-boiler furnace, fire is built 
upon the grate, and air is admitted through the grate 
into the fuel, the oxygen of the former being needed 
to support the fire. It is, however, a wellknown 
fact that not one-third of the amount of oxygen re- 
quired for perfect combustion passes through the 
body of the fuel; this produces carbonic oxide, 
which usually passes away unconsumed, since the 
flames of the fire impinge directly on the boiler- 
plate, the temperature of which (at common steam 
pressure) is below 400 degr. Fahr. Consequently 
the unburnt gases escaping from the fuel pass on 
out of the chimney and are wasted. If we wish to 
burn the carbonic oxide in a furnace, we should 
supply a certain weight of highly heated ox^'gen 



DISADVANTAGES. 21 

above the grates, but this can not be done in ordi- 
nary furnaces, since atmospheric air, the source of 
oxygen as a supporter of furnace combustion, is 
admitted through the registers in the furnace door. 
Besides the opening of the door in firing of fresh 
coal allows the cold air to rush in through the whole 
length of the furnace, depriving the walls of a great 
amount of heat and cooling down the interior space, 
so that considerable time must elapse after the doors 
are closed before the fire is glowing and the former 
high temperature in the furnace is restored. This 
disadvantage of the ordinary steam-boiler furnace 
not only wholly prevents the combustion of gases 
at the time, but also causes a direct loss of fuel, as 
will be perceived by the following. 

In all soft coals, there are found compounds of 
carbon and hydrogen known as hydro- carbons, 
which must also pass into the gaseous condition 
before being burned. If these hydro-carbons, such 
as pitch, tar, naphta, etc., are mixed on first -issuing 
from the coal with a large quantity of air, these in- 
flammable gases are completely burned with a trans- 
parent blue flame, producing carbonic acid and 
steam, but if raised to a red heat, before being 
mixed with air enough, they disengage carbon in 
fine powder, and the higher the temperature, the 
more carbon they disengage. If this disengaged 
carbon is cooled below the temperature of ignition, 
before coming into contact with oxygen, It consti- 
tutes, while floating in gas, smoke, and when depos- 
ited on solid bodies, is soot. But if this disengaged 
carbon is maintained at the temperature of ignition, 
and supplied with oxygen sufficient for its combus- 
tion, it burns, while floating in the inflammable gas, 
with a red, yellow, or white flame. The flame from 
fuel is the larger, the more slowly its combustion is 



22 EXPERIMENTS. : 

effected, and with the colors of flame given above, 
as the combustion is less or more complete. An 
example of this is found* in the use of common il- 
luminating gas, when burned with a "Bunsen" or 
with a common burner. The chilling of the gaseous 
hydro-carbons, which are driven off from the solid 
pieces of coal by the heat developed, takes place in 
two ways in ordinary furnaces: either by coming 
in contact with a cold body as the iron of the boiler, 
or by finding too much cold air in the furnace. 

But have there been no devices to avoid these 
disadvantages and utilize this waste ? 

For the past thirty years, or more, experiments 
have been made to utilize this immense waste. 
Various experiments have been made to save this 
loss by the use of atmospheric air above the fire, 
the principal method being to introduce cold air. 
But this results in a loss, for the air must be raised 
in temperature to about eight hundred degrees of 
Fahr. to produce combustion. Later furnaces have 
been invented to preheat the air to a high degree, 
before joining it with the gases, and thus save taking 
so many units of heat from the flames. 

Various devices have been adopted to preheat 
the air. Some have admitted air through the 
bridgewall. Others have admitted the same by 
small flues in front and then conducted it through 
a number of horizontal expanding ducts, in which 
it passes backward and forward, until finally in a 
heated state, it enters at the sides and bridgewall 
of the furnace, and unites with the product of com- 
bustion. Whenever this was done, it was invariably 
at the cost of economy, because the brick walls ab- 
sorb heat from the gases and flames, and conduct 
it to the cold air passing through the airducts. 
Others have adopted the firecla}^ arches over the 



SMOKE-PREVENTING. 23 

fire space and back of the bridgewall to admit air 
above the grates. Steam jets have been placed 
above fire-front door and' back of bridgewall to 
force air and steam above grate. 

Most of these devices, however, have progressed 
very little in the accomplishing of the aim for which 
they were intended, and the immense waste is still 
going on. 

Smoke burning, or smoke preventing rather, is 
also attracting no little attention at present in this 
country, owing largely, perhaps, to the stringent 
laws on the subject enforced by some cities against 
the nuisance. It will, however, not be far from the 
truth to say that there is no successful device in use 
for smoke prevention, although strong claims are 
made for several. We shall refer to ordinary illu-, 
minating gas in order to show the causes of smoke 
and the reason why smoke-preventing devices have 
hitherto met with such poor success. 

Ordinal illuminating gas is made by heating coal 
in a closed vessel. The gas thus given off is that 
which in a furnace is needed to supply the necessary 
air and heat to effect combustion. This gas un- 
mixed with the air, will not burn, but when allowed 
to escape from a burner and supplied with the air 
in the room, it ignites, if a flame be touched to it. 
If a burning gas jet be exposed to draught from an 
open door or window, it smokes, because the supply 
of air is too great, the heat is insufficient; and it 
therefore appears that a too plentiful supply of air 
is as detrimental as too little. It is also stated that 
if coal gas and air be placed together in a vessel, 
it will take considerable time for it to mix thor- 
oughly unless assisted by violent agitation or me- 
chanical means. When the great velochyv of the 
gases in the furnace and the short time occupied 
3 



24 ENORMOUS WASTE. 

by them in passing from the coal to the flues is 
considered, the difficulty of mixing the air with 
them will be appreciated. It is also necessary to 
mix the air with the gases as close to the fire as 
possible in order that the mixture may have suffi- 
cient heat to allow of burning. All smoke prevent- 
ing devices which allow of the admission of air at 
the top of the fire box or in another chamber are 
necessarily ineffective to a greater or less extent 
owing to this fact, that is, the mixture is too cool 
to burn. Gas is given off in variable quantities, 
depending on, whether the coal is green, half, two- 
thirds, or more burned, and the supply of air must 
be in proportion. Hence, for perfect combustion 
of the gases and without smoke, the supply of air 
should constantly change, which is manifestly im- 
possible in ordinary furnaces. Smoke once formed 
is not inflammable, and the term "smoke burning" 
is absurd. 

The enormous waste, imperfectly understood by 
most men of science, is scarcely thought of by the 
great mass of people. The composition of the air 
is also very unfavorable to a good result, since it 
is but poorly adapted to combustion, because its 
oxygen, the only combustible element in it, con- 
stitutes but one fifth of its volume, while the ni- 
trogen, representing four fifths, is not only useless 
in combustion, but retards it and absorbs a large 
proportion of the heat of the fire. Under skillful 
superintendence the quantity of air used is 150 cubic 
feet to each pound of coal, or 300000 cubic feet for 
a ton. Therefore, if an establishment fire about 
seven tons of coal per day, 2100000 cubic feet of 
air would be required for combustion. Of this vast 
amount 1680000 cubic feet l are useless nitrogen 
passing into the furnace cold and out of it hot. 



THE REFORMATION. 25 

If the excessive use of air is unavoidable even in 
♦the most perfect furnaces under scientific super- 
vision, and occasions so extensive a loss in heat, it 
may be inferred how great a waste of heat must 
occur from this single cause in furnaces and chim- 
neys imperfectly constructed and under the ignorant 
management of unskillful men.* 

On the other hand if too little air is used a partial 
conversion ensues, and a large proportion of most 
valuable combustible gases drifts out of the furnace 
into the atmosphere. 

But how may the reformation of so glaring an 
evil be effected, and both the primary and secondary 
loss, already explained, be reduced? 

The "National Electric Furnace" will effect this 
reformation. Instead of air it will introduce a mix- 
ture of steam, hot air, and gases, into the fuel, 
by which the bad influence of nitrogen is greatly 
avoided, because the water, unlike the air,*is com- 
posed entirely of combustible gases, oxygen and 
hydrogen. The following pages will give an accu- 
rate description of the furnace, then its operation 
will be shown, and lastly a few directions will be 
added, followed by a few remarks on the advan- 
tages of the furnace. 

* It is true, the heat is not wholly lost, but is required in the 
chimney of ordinary boiler furnaces for producing a draught. For 
the chimney is a kind of blower, the same as a chimney on a coal- 
oil lamp, the more heat in a chimney, the more air forced through 
the furnace. But, as we have already stated, the velocity of the 
air in passing through the furnace, results in the escape of a great 
amount of. valuable gases, which are carried off by the air without 
being ignited, and are therefore wasted. If, however, too little air 
is used, the combustion is too slow, and the heat in the furnace and 
flues insufficient to burn the gases and hydro -carbons. 

So it is readily seen that a chimney is an expensive apparatus. 
Just look at it; the black clouds and fogs of smoke in the atmos- 
phere over our largest cities, what are they? Nothing else but 
wasted coal. It is stated that in an ordinary furnace the waste of 
fuel is all the way up from 25 to 50 per cent. 



THE 






£K 



M Mi • 

aticmal fMecfcrtc wwcnacz* 



3>#4< 



AIMS AND ADVANTAGES. 

1. Will do about double the work of any ordinary 
good furnace. 

2. Evaporate more water per pound of coal. 

3. Burn more coal per square foot of grate. 

4. Increase in horsepower per square foot of grate. 

5. "Will greatly improve the burning of anthracite 
coal. 

6. Cause even draught. 

7. Secure even temperature. 

8. Easily adjust the amount of oxygen and gases. 

9. Avoid an excess of heat. 

10. Steam quicker and easier. 

11. Generate drier steam (more powerful). 

12. Occasion no waste of fuel or heat. 

13. Will never permit cold air to reach grate bars 
or flues. 

14. Grate bars will not warp. 

15. Require no poking. 

16. Cause no clinkers. 

17. Need no flue cleaning. 

18. Less attention necessary for firing. 

19. Leave lighter, finer ashes. 

20. Produce a continual circulation of gases. 



THE NATIONAL ELECTRIC FURNACE. 27 

21. Create a more uniform temperature in furnace, 
flues, etc. 

22. Convert steam (exhaust steam) into gaseous 
condition. 

23. Make use of mixing apparatus and fan as a 
regulator of furnace combustion. 

24. Avoid an excessive heating of incombustible 
air (Nitrogen). 

25. Make the heat and flame more intense through- 
out the boiler-flues. 

26. Prolong the life of the boiler. 

27. Protect the neighborhood against the annoying 
and deleterious clouds and fogs of smoke. 

28. Dispense with large expensive chimneys. 

29. Occasion no back-pressure on engine by reason 
of the suction of the fan drawing into the mixer 
the exhaust steam from the engine, thus creating 
a partial vacuum in the exhaust pipe. 

30. Can be readily adapted to all types of boilers. 

DESCRIPTION. 

The object of this invention is to provide a new 
and improved furnace for steam boilers and for 
other purposes, in which a complete combustion of 
the fuel is accomplished by introducing a mixture 
of steam, hot air, and gases into the fuel. 

The invention consists in a specially constructed 
furnace and chimney, and in an apparatus for for- 
cing a mixture of hot air, steam and gases into the 
fuel. 

The invention also consists of various parts and 
details, as will be fully described hereinafter. The 
following five cuts show different views of the fur- 
nace, and will serve to illustrate the subsequent de- 
scription. 



NATIONAL, ELECTRIC Fl'RXACE. 







FIG. 1. 



THE NATIONAL ELECTRIC FURNACE. 



29 



SECTIONAL PLAN VIEW. 




Fig. 2. 



30 



THE NATIONAL ELECTRIC FURNACE. 



CROSS SECTIONAL ELEVATION AND SECTIONAL ELEVATION 
OF CHIMNEY. 




Fig. 4. 



Fig. 3. 



THE NATIONAL ELECTRIC FURNACE. 
CEOSS SECTION. 



31 




32 DESCRIPTION. 

Figure 1 is a longitudinal, sectional elevation of 
the improvement. 

Figure 2 is a sectional plan view of the same on 
the line x — x Figure 1. 

Figure 3 is a cross sectional elevation of the same 
on the line y — y Figure 2. 

Figure 4 is a sectional elevation of the chimney 
on the line z — z Figure 2. 

Figure 5 is a cross section on the line v — v Figure 1.. 

The steam boiler A (Fig. 1), of an} T approved con- 
struction, is mounted in the furnace B provided with 
the usual grate bars C, the ash-pit D, the doors D 1 , 
leading to the ash-pit, and the doors E 1 opening iuto 
the combustion chamber E above the grate bars. 
The bridge wall F, at the inner end of the grate 
bars C, is provided with a partition wall G, which 
divides the furnace into two main compartments, the 
combustion chamber E and the hot air chamber H. 
The bridge wall F is provided with several flues F 1 , 
which commence under the grate bars C, run inward 
and then upward, and open into the combustion 
chamber E at the rear of the grate bars C. 

In the side walls B 1 (Fig. 5) of the furnace B are 
ducts or flues I 2 , which lead from the ash-pit D to 
the vertical passage I 1 , which connects at its top by 
the flue I with the combustion chamber E. The 
flue I 2 is provided with a damper I 3 , which can be 
opened or closed from the front of the furnace by 
a damper rod I 4 (Fig. 1). 

Into the bottom of the ash-pit D (Fig. 2) opens a 
flue or duct J which connects with the mixing appa- 
ratus K placed on the outside of the side wall B 1 , and 
connected with the hot air chamber H and a chim- 
ney M by the transverse channel N. The latter is 
arched at two or more places, so as to reduce the 
opening X 1 leading from the hot air chamber H into 



OPERATION. 33 

the channel N. The hot air chamber H is provided 
with a bottom H 1 which is curved upward from the 
rear end toward the channel N, and is also provided 
with a door H 2 through winch ashes and cinders 
which accumulate in the hot air chamber H can be 
removed. 

The mixing apparatus K (Fig. 3) consists of a fan 
K 1 , which is rotated in any convenient manner, into 
which apparatus opens a pipe K 2 admitting steam, 
and it is also provided with an opening K 3 , through 
which air can pass into the fan from outside. The 
heating of the journal box O of the mixing appa- 
ratus K is prevented by the circulation of cold water 
around the fan shaft O 1 in the journal box O, said 
water being supplied by a small pipe O 2 and drawn 
off through the pipe O 3 . 

The channel N is provided at its entrance to the 
chimney M with a hinged damper P operated from 
the front of the furnace by the damper rod P 1 
(Fig. 1). The chimne}^ M is provided on its three 
outer sides with doors Q, Q 1 , and Q 2 (Fig. 3 and 4), 
of which the door Q (Fig. 3) leads directly into the 
central chimney opening M 1 , while the doors Q 1 
and Q 2 (Fig. 4) connect with the vertical side flues 
R, which open into the central opening M 1 , by 
means of the apertures R 1 . 

The opening of the flue J (Fig. 1) into the ash-pit 
D can be closed by the door S so as to prevent ashes 
and cinders from falling into the said flue when being 
removed from the ash-pit. 

The operation is as follows : 

The flames and heated gases from the fire on the 
grate bars C rise and lap upon the sides of the 
boiler, and on the front end of the same in the com- 
bustion chamber E. The heated gases and flames 



34 OPERATION. 

enter the boiler flues A 1 at the front end of the 
boiler A, and, passing through the same, enter the 
hot air chamber H, from which they are drawn up 
the inclined bottom H 1 into the channel N by the 
suction of the fan K 1 and the draught of the chim- 
ney M. That portion of the unconsumed products 
of combustion which passes into the chimney is 
drawn thereinto by the draught or circulation set 
up by the action of the fan, the same consisting in 
the current of air forced from the fan through the 
pipe J, into the chamber D, through the passages 
I 2 , I 1 , I, into the chamber E, thence through the 
boiler tubes and into the hot air chamber H, whence 
the same will be forced through the opening N 1 
into the channel N, above the damper P, and into 
the central opening or passage M 1 of the chimney, 
passing thence into the open air. 

The remainder of the heated products consisting 
of combustible gases and hot air, passes into the 
mixing apparatus K, where it is mixed by the action 
of the fan K 1 with the steam (generally exhaust 
steam) entering through the pipe K 2 and with the 
fresh air entering from the chimney M. This mix- 
ture is then diverted into the flue J and enters the 
ash-pit D, from which part of it passes directly 
through the grate C into the burning fuel, part 
enters the flues F 1 and passes from the rear into 
the combustion chamber E and over the fuel on the 
grate bars C, and part of the mixture passes into 
the side passages I 1 and up through the same and 
enters the combustion chamber E by means of the 
openings I. The amount of the mixture which 
enters the side passage I 1 can be regulated by the 
damper I 3 . The heated products or gases pass 
then from the combustion chamber into the flues A 1 
of the boiler A, as before described. The outside 



' DIRECTIONS. 35 

air is drawn into the chimney by reason of the suc- 
tion of the fan, the same, as before stated, taking 
or drawing into the mixer a portion of the products 
of combustion and forcing or sending it into the 
chimney as above described, thus creating a partial 
vacuum in the chimney, assisting the downward 
passage or entrance of the air from the side-ducts R 
of the chimney into the central opening M 1 thereof, 
while the inlet to the channel N from the chimne}' 
is of greater area than the inlet thereto from the hot 
air chamber H, whereby the cold or fresh air cur- 
rents which are heavier than the warm air currents 
will descend, passing closely along the sides of the 
chimney and the bottom of the channel N, under 
the valve P, whence it passes into the suction side 
of the mixer, thus effecting the aforesaid result. 

Air from the outside can enter the chimney M by 
the side doors Q 1 and Q 2 , and after passing up the 
side flues R enters the central opening M of the 
chimney, forced downward in the same by the suc- 
tion of the fan K 1 , and is heated in this downward 
motion by the incombustible and unconsumed gases 
passing up the central shaft M 1 , as before described. 

The complete combustion of the fuel is thus at- 
tained by our improved furnace, the combustible 
gases being forced from the hot air chamber into 
the combustion chamber, and being additionally 
charged with a mixture of steam and air. 

Directions : 

In starting the furnace, build your fire upon the 
grate as usual. Open the damper in the channel to 
the chimney to give sufficient draught, and close 
the doors in the vertical side flues of the chimney. 
See that the dampers in the flues of the side walls 
are closed. Admit the air through the ash-pit doors 



36 WASTE OF HEAT AVOIDED. 

to support combustion. When sufficient steam is 
generated for the proper pressure to start the en- 
gine, set the dampers and then start the mixing 
apparatus or fan. When it is in operation, open 
valve in exhaust pipe to admit a sufficient volume 
of steam into the mixer. Keep the doors in the 
furnace front closed. Eegulate the damper in the 
air-ducts of the side walls to admit more or less of 
the mixture above the grate. Set the damper to 
chimney in its proper place to admit a sufficient 
volume of fresh air and to allow the unconsumed 
and incombustible air to escape. Be careful not to 
waste. The engineer will soon learn its working. 

The great waste of heat avoided. 

In an ordinary furnace, the gases and flames pass 
on over the bridge wall to the rear end. The stream 
of heat and flames heats the boiler above and the 
bottom floor of furnace below, the latter absorbing 
considerable heat for no benefit whatever. The 
artificial forced draught in the "National Electric 
Furnace," however, will assist the fire in the com- 
bustion chamber by compelling the flames to lap 
upon the sides and end of the boiler, so that the 
heat will be forced through the flues and generate 
steam (dry steam) with greater effect. 

The exhaust steam utilized. 

In most all furnaces in which steam is used for 
power, the exhaust steam is more or less wasted, 
except what is used for heating feed-water, and in 
some cases, for heating the building, etc. In an 
ordinary good engine, where power is used, to an 
extent, about one third, more or less, of the exhaust 



EXHAUST STEAM UTILIZED. 37 

steam is sufficient to heat the feed-water,* while 
two thirds, more or less, can be made useful for 
fuel, the hydrogen to burn, and the oxygen to sup- 
port combustion. Why is not all of this heat and 
gas utilized instead of being wasted? The cause is 
that hitherto there has been no successful device to 
utilize it. The "National Electric Furnace" for 
steam boilers, however, will utilize nearly all of the 
gases and heat, that have hitherto been wasted. 
Instead of air, it will make use of a mixture of 
steamy hot air, and gases for combustion. The 
heated product of combustion in the furnace, con- 
sisting of combustible gases and hot. air, is forced 
into the mixing apparatus, where it is mixed with 
the exhaust steam by the action of the fan. The 
hot air and gases forced into the mixing apparatus 
absorb the steam, as it enters the apparatus. This 

* The Fuel Economizer which has been largely used in England, 
has been improved and adopted in this country. It is confidently 
presented to the public as the very best thing of the kind at present 
known. There are two sources of waste in all steam boilers which 
may in a measure be made to neutralize each other. The gases 
going to the chimney carry off on an average, according to good 
authority, 31 percent'moreor less of the fuel, in the most econom- 
ical boilers. The feed-water has to be heated from the normal 
temperature to that of steam before evaporation can commence, 
and this is generally done at the expense of the fuel which should 
be utilized in making steam. This temperature, at 75 lbs. pressure, 
is 320-, and if we take «0 r as the average temperature of feed, we 
have 260 units of heat per pound which, as it takes 1151 units to 
evaporate a pound from 60°, represents a loss of 22.5 percent of 
fuel. All of the heat, therefore, which can be imparted to the feed- 
water, from the waste heat in the escaping gases, is just so much 
saved. Xow the Fuel Economizer consists of a series of vertical 
tubes placed in a brick chamber, which forms part of the flue be- 
tween the boiler and the chimney, and through which all the hot 
gases are caused to pass. The feed-water is forced and enters at 
one end of the connecting pipe, then travels through a series of 
vertical tubes, so that it is possible to heat the water very nearly 
to the temperature of the escaping gases before it flows to the 
boiler. 

The exhaust steam, however, fnnn nearly all steam engines is 
mostly wasted, as has been stated above, but in our case, if the 
Economizer be adopted for heating the feed -water, the exhaust 
steam cduld be utilized for combustion to an extent and thus 
nearly all escape gases saved. 



'38 COST OF FAN OUTWEIGHED. 

mixture is- then forced through and above the grate 
into the combustion chamber. Whatever part of 
the mixture is not ignited at the first circulation, 
on account of not having been thoroughly mixed, 
is forced through the flues mingled with other gases 
into the hot air chamber, and thence to mixer for 
second circulation, and so on. 

The cost of the fan quite outweighed by the 
saving. 

Objection may be raised regarding the cost of 
running the fan or a blowing engine. But the 
draught of the chimney assists the fan to raise the 
incombustible and unconsumed air out of the chim- 
ney, and the fan is, therefore, required to run at 
moderate speed only, less than if only atmospheric 
air were used to support combustion. Besides, the 
gain acquired by using an atmosphere of steam, 
hot air, and combustible gases in the National Elec- 
tric Furnace, and so avoiding the heating of a vast 
amount of incombustible air (nitrogen) which takes 
place in an ordinary furnace, nearly cancels the ex- 
penditure of running a fan or blower. Then another 
saving results from the mixture itself, since it cre- 
ates a new water-gas fuel (carburetted hydrogen) 
and produces a continual circulation in the furnace, 
the violent agitation by mechanical means mingling 
and mixing the fine particles of carbon and other vol- 
atile matters, and the product so created being con- 
tinually regenerated with a new supply of fresh hot 
air and steam, etc., as explained before. This 
combination of gases enables a more perfect com- 
bustion than takes place in ordinary furnaces and 
will accomplish a saving of fifty per cent, more or 
less. 



BACKPRESSURE DIMINISHED. 39 

The backpressure diminished. 

There is still another gain to overcome the cost 
of power to run the mixing apparatus. The blower 
(or fan) draws the exhaust steam from the engine 
and so diminishes the back pressure by creating a 
partial vacuum in the exhaust pipe.* This will 
clearly show that by using artificial draught and so 
utilizing all the wasted gases, the National Electric 
Furnace fully overcomes the cost of running the fan. 

The advantage of the "National Electric Furnace" 
of other furnaces with artificial forced draught. 

What advantage has the ' ' National Electric Fur- 
nace" of other furnaces with artificial forced 
draught? Other furnaces with artificial forced 
draught make use only of atmospheric air and pro- 
duce a great waste. They force large amounts of 
air through the grate, but the velocity of the air in 

* It is stated, that a condenser by condensing the exhaust steam 
from an engine, diminishes the backpressure by creating a partial 
vacuum behind the piston. This vacuum is generally spoken of as 
being of so many inches of mercury, eacli inch of mercury repre-. 
senting a diminution of half a pound in the backpressure. Thus, 
a vacuum of twenty-six inches means that the backpressure has 
been reduced thirteen pounds per square inch ; or, that instead of 
the engine working against a resistance equal to the pressure of 
the atmosphere (about fifteen pounds per square inch), it is work- 
ing against a resistance of only two pounds per square inch. A 
vacuum of twenty-six inches, however, can not always be obtained, 
but one of twenty inches may be safely assumed with almost any 
condenser. Diminishing the backpressure ten pounds per square 
inch has the same effect as adding ten pounds per square inch to 
the mean effective pressure of the engine. In other words, if an 
engine, while working against a backpressure equal to the press- 
ure of the atmosphere, has a mean effective pressure of thirty 
pounds, it will have a mean effective pressure of forty pounds per 
square inch when the condenser is attached. In this case, other 
things being the same, the engine would be able to do exactly one- 
third more work with the aid of the condenser than without "it. 

If a steam condenser, as above stated, has such effect, how 
much greater must the effect of a blower (fan) be, which forces 
the exhaust steam from an engine, thus creating a greater partial 
vacuum behind the piston than the condenser. 

4 



40 DIFFERENT ADVANTAGES. 

passing through the fuel being so great, the result 
is, that great volumes of gases pass on unconsumed 
and leave by way of the chimne3 r . The "National 
Electric Furnace," however, returns these products, 
mixes them with steam and air, forces them into 
the fuel at the required degree of heat, and so pro- 
duces perfect combustion. In this manner it ac- 
complishes an increase in horsepower per square 
foot of grate, burning more coal per square foot of 
grate, evaporating more water per pound of coal, 
and hence requiring less boiler and furnace space. 
It will, therefore, do double and more work in 
generating steam, will burn all kinds of fuel, and 
will greatly improve the burning of anthracite coal. 
The hydrogen gas given off in the burning of 
bituminous coal is that which in a furnace is neces- 
sary to supply the necessary air and heat to effect 
combustion. The mixture of steam, hot air, and 
gases consists greatly of hydrogen and thus gives 
to the anthracite coal that, which will make it more 
illuminous and increase its power. 

Other advantages. 

The operation of this furnace by mechanical 
means will also cause a uniform temperature, a 
steadier, evaporation, less firing, less labor, less 
wear and tear, and hence less repairs. 

The "National Electric Furnace" can be worked 

like other forced draught furnaces, or even like 

an ordinary steam-boiler furnace, as occasion 

requires. 

It is also quite obvious that the National Electric 
Furnace can be operated without the use of steam 
in the mixing apparatus. If, for instance, from 



PLANT MAY BE VARIED, ETC. 41 

any cause the entire exhaust steam should for the 
time being be required for other purposes, the supply 
of steam to the mixing apparatus can be simply cut 
off, and the apparatus will work on all the same, in 
such case performing the office of a blower of a 
natural forced draught furnace. Even the mixing 
apparatus may totally suspend operation, while the 
furnace performs its work like an ordinary boiler 
furnace by means of the draught of the chimney, 
with the advantage, however, that its combustion 
chamber and hot air chamber are separated, so that 
the air can not rush through the whole length of 
the furnace at once and carry off so much valuable 
combustible matter, as it does in ordinary steam 
boiler furnaces. 

The plant of the "National Electric Furnace" 
may be varied. 

The plant of the furnace may be varied in con- 
struction. The air ducts that connect the fan with 
the ash-pit can be placed underground and be made 
of brick or other material. The fan or mixing appa- 
ratus can be placed at any suitable place by ex- 
tending the air channel. The fan can be run by a 
belt from a near shaft. A mixing apparatus com- 
bined with a blowing engine, (See p. 42) now made 
at a very reasonable price, would be preferable. 
The chimney can also be a distance from the fur- 
nace by extending the air channel. Old chimney 
can be used. 

The "National Electric Furnace" may be adapted 
to any boiler. 

The improvement is not confined to one class of 
boilers only, but can be adapted to any boiler of any 



42 



BLOWING- ENGINE. 




The above illustration represents a fan combined with 
a blowing engine, which we highly recommend for adop- 
tion, whenever the latter is to be combined with the 
mixing apparatus of the "National Electric Furnace." 
In operating the furnace, especially the larger size, the 
work of the blower is most steady and regular, and the 
fan can be regulated at will to run at a high or low speed, 
according to the increase or decrease of combustion re- 
quired in the furnace for the evaporation of steam. These 
blowing-engines are superior to the common run of mill 
engines in point of strength and workmanship. They 
are made to stand twenty-four hours continuous work 
six days in the week, and to run at any speed without 
getting out of order. They are manufactured by different 
parties, the above engraving representing a style manu- 
factured by B. F. Sturtevant. Boston. 



BATTERY OF BOILERS. 



43 




44 



approved construction. The engraving (See p. 28) 
represents only one style, but all that is needed to 
adapt the improvement to boilers of various con- 
struction, is to arrange it so that the heat and flames 
will be applied to the heating surface in such a man- 
ner, as will be most effective. The boiler is simply 
mounted in the furnace ; the combustion chamber 
is to be built up with white fire brick, and the air- 
jets or flues in bridge- and sidewalls are to be made 
the size of one brick in height and width. 

The "National Electric Furnace" may be applied 
to a battery of boilers. 

The improvement can also be very readily applied 
to a battery of boilers, (Seep. 43) and with a marked 
better result in regard to the cost of operating it. 

By comparing the following tables, the advantages 
of the "National Electric Furnace" over ordinary 
good furnaces in the developing of horse-power,* 
etc., may be plainly seen. 

* When Watt began to introduce his steam engines, he wished 
to be able to state their power as compared with that of horses, 
which were then generally employed for driving mills. He accord- 
ingly made a series of experiments, which led him to the conclu- 
sion that the average power of a horse was sufficient to raise about 
33000 lbs. one foot in vertical hight per minute, and this has been 
adopted in England and this country as the general measure of 
power. 

Hence, if an ordinary Avell- constructed boiler can at a moderate 
heat furnish sufficient steam for pressure to drive an engine so 
that it will raise a weight of about 33000 lbs. one foot in vertical 
height per minute, it is said to be equal to about one horse-power. 

The best engines and boilers develop a horse power per hour by 
the consumption of two pounds of coal. But this is better than 
the average, and three lbs. of coal per hour for a horse-power is a 
more common result. 



NATIONAL ELECTRIC FURNACE. — TABLE. 



45 



The "National Electric Furnace" 

with artificial forced combustion ivill accomplish on 
an average 

per 20 Minutes: 

PROPORTION— Horse-power ; heating and grate sur- 
face ; coal consumed ; water evaporated ; steam generated ; 
two-thirds more or less of the exhaust steam converted 
into a mixture for fuel ; half of the combustible gases and 
hot air, more or less, taken from the hot air chamber ; 
total mixture forced into the combustion chamber. 





» 










a=2 


If analyzed 


Total. 




53 


d 




<u 





e3-^ 


for 


Consumption 






<2 a 

3 
C 


O 

O 
03 

3 
C 
CO 




13 

£3 
3 
O 
Pi 





s 

5 


2 . 

"•a 
11 

<S a 
IS 

3 


Sil 

III 

9 3 








1 


a 

a 


0. j> 

■r. — 5 

|og 

■g 2 a 

s ■" 

3 


la , 

!|1 

m 


•52.2 
all! 

MS* 


111 


1 


10 


% 


2M 


1 


1700 


1133 


755 


378 


1133 


2266 


5 


50 


1% 


12H 


5 


8500 


5665 


3775 


1890 


5665 


11330 


10 


100 


&A 


25 


10 


17000 


11330 


7550 


3780 


11330 


22660 


20 


200 


7j| 


50 


20 


34000 


22660 


15100 


7560 


22660 


45320 


30 


300 


11% 


75 


30 


51000 


33990 


22650 


11340 


33990 


67980 


40 


400 


15 


100 


40 


68000 


45320 


30200 


15120 


45320 


90640 


50 


500 


22)| 


125 


50 


85000 


56650 


37750 


1S900 


56650 


113300 


60 


600 


150 


60 


102000 


67980 


45300 


22680 


67980 


135960 


80 


800 


30 


200 


80 


136000 


90640 


60400 


30240 


90640 


181280 


100 


1000 


37^ 


250 


100 


170000 


113300 


75500 


37800 


113300 


226600 



Xote— The above calculations hare been gained through some 
reliable information, and from scientific papers. They were theo- 
retically calculated, and the figures will give nearly the results, 
although these may vary in figures a little below or above the 
amount. The furnace can be regulated more or less by mechanical 
operation. 



46 



ORDINARY FURNACE. — TABLE. 



An Ordinary Good Furnace 
with natural draught will accomplish on an average 

per 60 Minutes: 



PROPORTION — Horse-power ; heating and grate sur- 
face; coal consumed; water evaporated in pounds, gal- 
lons, or cubic it.; amount of atmospheric air required 
for combustion, in cubic feet; volume of oxygen {\ of 
atmospheric air) supporting combustion, in cubic feet; 
volume of nitrogen in cubic feet (f of atmospheric air) 
as a waste of heat passing into the furnace cold and out 
of it hot. 





a 


| 




. 


. 


r 


is 


If analyzed 


£ 


■p 


i£ 


i 


3 


| 


- 




contains 




■ — • 


O 




•a 




«. 





1 








||| 


Hi 








2 
















1 


g, 


= 





■3 
-5 


1 


-§ ^ 


~ = = 


= i| 




X 


X 








° 


~ 


C = 


£ = 


i 


15 


Vs 


VA 


62% 


iy 2 


1 


1125 


225 


900 


5 


75 


3% 


37% 


312 V 2 


37% 


5 


5625 


1125 


4500 


10 


150 


V4 


75 


625 


75 


10 


11250 


2250 


i:ooo 


15 


•225 


9% 


112% 


937% 


112% 


15 


16875 


3375 


13500 


20 


300 


12% 


150 


1250 " 


150 


20 


*22500 


4500 


18000 


25 


375 


15p 

18% 


187% 


1562% 


187% 


25 


28125 


5625 


22500 


30 


450 


225 


1875 


225 


30 


. 3:3750 


6750 


27000 


40 


600 


25 


300 


2500 


300 


40 


45000 


9000 


36000 


50 


750 


31 x 4 


375 


3125 


375 


50 


5(3250 


11250 


4500O 


60 


900 


37% 


450 


3750 


450 


*o 


67500 


13500 


54000 


SO 


1230 


50 ~ 


600 


5000 


600 


80 


90000 


18000 


72 M0 


100 


1500 


62% 


750 


6250 


750 


100 


112500 


22500 


90000 



Note.— These calculations are generally believed and accepted; 
they have been collected from reliable sources with much care. 



NATIONAL ELECTRIC FURNACE PATENTED. 47 

We are aware of the difficulty of overcoming old 
established customs. The time, however, is not 
far, when manufacturers and steam users, instead of 
diffusing their valuable combustible gases into the 
atmosphere, will gladly adopt a device for utilizing 
all that is now wasted in regard to fuel and so do 
away with the smoke nuisance. As long as there is 
no device, however, "smoke ordinances," which 
some cities have adopted, can not and will not be 
enforced. The "National Electric Furnace," how- 
ever, will, as we sincerely hope, through its merits 
soon convince the public of the possibility of pre- 
venting all of the waste going on in combustion and 
of doing away with the smoke nuisance. 

The "National Electric Furnace Co." owns the 
above furnace, and its rights are controlled and 
protected under Letters Patent No. 350245, granted 
to G. Hasecoster, October 5th, 1886. Plans, spec- 
ifications, etc. will be furnished upon application. 
For further information apply to "National Electric 
Furnace Co.," St. Louis. 



Artificially Forced Combustion. 



The idea of making use of artificial draught for 
the purpose of increasing the amount of coals ca- 
pable of being burned per square foot of grate, is 
by no means a new one, as will be shown by the 
following, which we have abstracted from an article 
in the "Mechanical Engineer." 

"The value of space in the merchant steamer for 
carrying cargo, and in the vessel of war for coal 
•capacit}^, whereby her ability to keep the sea or 
steam long distances may be increased has induced 
many experiments with different methods of artifi- 
cial draught. Of the steam-jet in the smoke-stack 
and beneath the grates we have had an endless 
variety, and of the air-blast at both the above 
places there have been various plans. While these 
have been more or less successful in improving the 
draught, it has been generally at a complication of 
detail and waste of steam ; so it may be asserted 
that there are but two practical plans that effect 
the purpose of increasing the amount of coals ca- 
pable of being burned per square foot of grate. 

"At this present time great exertions are being 
made to reduce both weight and space occupied by 
the boilers and coals. In a marine engine the 
amount of coal burned per square foot of grate is 
a measure of the efficiency of the machine^, for, 
no matter how economical the engines may be, if 



ARTIFICIALLY FORCED COMBUSTION. 49 

the combustion is slow, a large amount of grate 
surface is necessary, and the consequent weight of 
the boiler excessive. Most of our American sea- 
going steamers have boilers designed to burn an- 
thracite coal with natural draught, which gives from 
5 to oh horse-power per square foot of grate, while 
foreign vessels, using bituminous coal, obtain from 
7 to 8 horse-power ; and in some of the large At- 
lantic liners, using the best quality of Cardiff coal, 
as high as 10 horse-power per square foot of grate 
has been attained. We now learn that the English 
government designs increasing this performance by 
fitting air-tight fire-rooms to the merchant vessels 
recently purchased by them. The most successful 
use of artificial draught seems to be obtained by 
making the fire-rooms air-tight and providing blowers 
sufficient to maintain the air-pressure required. 

' ' The air-supply is obtained from blowers receiv- 
ing the air from the out-side and delivering it into 
the closed space of the fire-room. In some vessels 
it is so arranged that the ventilation of the hull is 
secured by the same blowers receiving the air 
through ducts from the holds, or living quarters of 
the vessel — a rather questionable arrangement, 
unless the blowers are of extraordinary capacity, 
and this on account of the difficulty of getting a 
sufficient supply of air to them. The average con- 
sumption of coal in a marine boiler will not exceed 
12 lbs. of anthracite or 16 lbs. of bituminous coal per 
square foot of grate, which is raised to 18 or 20 by 
the use of the ordinary jet. But the large amount 
of steam used, compared with the gain in horse- 
power, makes the cost of an i. h. p. in coal ex- 
cessive." 

The following description of applications of 
forced draught on the closed ash-pit system, by 



50 ARTIFICIALLY FORCED COMBUSTION. 

J. R. Fothergill, M. I. N. A., published in the 
"Mechanical Engineer" will without doubt be of 
interest to the reader, and will, as we hope, serve to 
convince him of the feasibility of our project. The 
description referred to being rather minute, we, 
therefore, do not give in the following the entire 
article, but only an abstract including those points, 
which will mainly serve to illustrate our idea. 

"In September, 1884, the writer applied forced 
draught to the boiler of the s. s. '-Marmora,'' which 
ran with considerable success till she became a total 
wreck. The 'Marmora's' boiler was built in 1874. 
The two bottom furnaces entered one combustion 
chamber, and it was not, therefore, a good subject 
for experiment. The engines of this steamer were 
compound direct-acting; cylinders, 25Mn. by 51 J 
in.; stroke 33 in., and 65 lbs. pressure; i. h. p. 
400. Boiler: length 8 ft. 8^ in., diameter, 14 ft. 
3 in. ; four furnaces: length, 6 ft. 2 in., diameter, 
3 ft. 1 in. Total heating surface, 1,700 sq. ft., in- 
cluding 283 3-in. tubes. The fan and engine were 
placed in a recess at the side of the boiler. The 
fan was driven by a belt, and the exhaust steam of 
the engine carried to the condenser of the main 
engines, or discharged into the waste steam pipe. 
Having no actual data to work upon, the arrange- 
ment fitted to the front of the boiler was specially 
designed to facilitate its ready removal should the 
experiment prove a failure. The fan was connected 
by a pipe to the square receiver running across the 
boiler front, to which was attached a lower receiver. 
From different points of these receivers connections 
were made to the closed ash-pits by short pipes, 
fitted with valves to regulate or shut off the supply 
of air to each or all of the fires, as might be re- 
quired. From the ash-pits the air passed through 



ARTIFICIALLY FORCED COMBUSTION. 51 

the dead-plates to the perforated baffles on the fur- 
nace fronts, and this supply of air was likewise reg- 
ulated by a valve under the dead-plate. 

' ' Before deciding the pressure at which the air 
should be maintained, consideration must be given 
to the particular work the ship is required to do. 
If it is a question of keeping down the weight, and 
getting speed Regardless of consumption, such as 
required in the navy, a high pressure must be main- 
tained. In the mercantile marine, especially with 
cargo steamers, economy is of the first importance, 
and thus we endeavor to evaporate the greatest 
quantity of water' per pound of fuel consumed ; 
whereas in the torpedo boat it is a question of 
evaporation, and not of wasted fuel. In the ' Mar- 
mora,' we carried from f-in. to £-in. water gauge 
pressure in the ash-pits, depending on the condition 
of the fires, and the amount of clinker formed. This 
pressure allowed the air to enter with sufficient force 
through the perforations at the end of the ash-pits, 
and likewise through the baffles at the furnace 
fronts, thus maintaining a pressure in the furnace 
which a little more than balanced the ascending 
gases in the funnel. 

From experience, the writer finds f-in. to f-in. 
water pressure gives the most economical results. 
With this pressure we do not unduly force the com- 
bustion, or cause a rapid delivery of the gases up 
the funnel at a high temperature with much loss of 
heat ; in fact, we maintain a constant and regular 
draught equal to what is experienced with natural 
draught in a strong gale. As the air delivered under 
pressure penetrates up through the fuel, and enhan- 
ces the combustion, it is necessaty to reduce the grate 
surface, and use thicker fires. In the case of the 
^Marmora,' we shortened the fire bars 1 ft. 3 in., re- 



52 ARTIFICIALLY FORCED COMBUSTION. 

during the total grate area 15.42 square ft., equal to 
29.4 per cent., and increased the consumption per 
sq. ft. of grate per hour from 15.68 lbs. to 21.29 lbs. 
The amount of air delivered below the grate should 
be just sufficient to gasify the coal to carbonic 
oxide, and meet the requirements of the hydrogen 
in its conversion to steam. As the carbonic oxide 
is evolved, it should immediately take up another 
portion of oxygen from the air supplied at the fur- 
nace front or behind the bridge, and thus produce 
carbonic acid. The manner in which the delivery 
of the air takes place at the furnace front and be- 
hind the bridge, is of very great consequence, and 
it is advisable most strongly to draw attention to 
this in particular. If the air is admitted in a body 
or sheet, it cleaves its way through the gases, does 
not mingle with them , and produces a cooling effect ; 
but, if the air is broken up, by passing through 
small holes, into innumerable jets, it, as it were, 
stirs up the gases, thoroughly mixes and combines 
with them, without reducing their temperature ; 
producing the most effective result in the forma- 
tion of carbonic acid. It will thus be seen how 
important it becomes to break the air up into jets 
before admission to the gases, for on this depends 
the quantity admitted, and thus the efficiency. 

"In the ' Marmora' we averaged about 18 lbs. of 
air per pound of coal consumed. In supplying 
forced draught to an ordinary boiler, or one not 
specially designed for such purpose, the velocity 
of the gases must be regulated by a damper in the 
funnel, otherwise the area through the tubes and 
of the funnel might be such that a pressure of air 
could not be maintained unless a very large quan- 
tity, much in excess of that required, was supplied. 
The damper should be placed in such position as 



ARTIFICIALLY FORCED COMBUSTION. 



53 



will maintain the air pressure, and allow the gases 
to escape in such quantity as will comply with the 
requirements of the air supply. In the 'Marmora' 
the damper, half-closed, gave the best results. The 
actual result of the application of forced draught to 
the ''Marmora,' based on a comparison of an aver- 
age of eleven voyages under natural draught im- 
mediately prior to the application of forced draught, 
and eleven voyages with forced draught, which the 
steamer made before being wrecked, is as follows : — 

SUMMARY RESULTS. 



Condition. 


Dist'ce in 
knots. 


Days 
steaming. 


Knots 
per hour. 


Consump- 
tion p. day 
steaming" 


Total cost 

of coal 
p. voyage. 


Natural draught prior 


3168 
3102 


16.81 

16.74 


7.85 
7.72 


8.81 


£ s. d. 

78 9 5 


Forced draught after 


8.58 U 12 10 






Difference 


66 


.07 


.13 


.23 


33 16 7 



This table shows the consumption per day steaming. 
The distance, time, and speed per voyage were prac- 
tically the same in each case ; but there was a saving 
of 43 per cent, effected in the cost of the bunker 
coals per voyage, equal to £33, 16s. , 7d. This saving 
was entirely due to the use of a cheap and inferior 
coal, which we were able to consume with forced 
draught to the same efficiency as a high class coal 
with natural draught. In striking the above aver- 
ages, no allowance whatever has been made for bad 
weather, much experienced in this trade, nor for 
other incidents ; but the data are entirely taken 
from the actual work done, as given in the log 
books. In the ' Marmora' the air supply was drawn 
from the stoke hole, and its temperature ranged 



54 ARTIFICIALLY FORCED COMBUSTION. 

from 70° F. to 90° F. In some systems of forced 
draught the air is made to circulate through tubes 
or passages, etc., which are heated by the waste 
gases as they. pass to the funnel. There can be no 
question that each degree of heat so obtained and 
returned to the furnace must be a distinct gain, in 
that it saves reducing the furnace temperature by 
the amount of heat added to the incoming air. 

' ' The specific heat of water is four times greater 
than that of air ; therefore, if air were used instead 
of water for the ordinary purposes of condensation, 
we should require 3369 cub. ft. of air to do the 
same work as 1 cub. ft. of water, assuming the 
temperatures to be the same in each case, 62° F. 
Weight for weight, and other conditions the same, 
the capacity of water for heat is four times that of 
air. The question thus arises, could not the heat 
of the waste gases be utilized to better advantage 
in raising the temperature of the feed water? 

"The saving effected in the '■Marmora,' which, 
in round figures, may be stated at £350 per annum, 
decided us, when building the s. s. 'Stella' fitted 
with triple expansion engines, and having two large 
boilers of 140 lbs. pressure, to apply forced draught 
to the boilers. This steamer trades to India, and 
as the arrangements with the various coaling sta- 
tions are to supply best Welsh coal, the economy 
to be sought in the application of forced draught 
must be in consuming a high class coal to greater 
evaporative efficiency, viz., for the same amount of 
water evaporated and steam produced, the coal con- 
sumption should be materially reduced. 

"This steamer has just returned from an Indian 
voyage, her dead weight carrying capacity being 
3800 tons, average speed 9J knots, on a consump- 
tion of 13.5 tons ordinary north country coals per 



USEFUL INFORMATION. bb 

day steaming, which is certainly a most successful 
achievement, working out to 1.4 lbs. per i. h. p. 
The writer believes the ' Stella' is the first instance 
of a triple expansion engine having the boilers fitted 
with forced draught, and also that the 'Marmora' 
was the first instance in which forced draught on 
the closed ash-pit system was applied to a boiler 
which had been for some time in use under the 
ordinary conditions of natural draught, and ran 
the same for eleven continuous voyages with con- 
siderable success." 



USEFUL INFORMATION. 



A gallon of fresh water weighs 8 J lbs. , and con- 
tains 231 cubic inches. A cubic foot of water weighs 
62^- lbs., and contains 1728 cubic inches or 1\ 
gallons. 

Each nominal horse-power of a boiler requires 
1 cubic foot of feed-water per hour. 

One square foot of grate will consume on an 
average 12 lbs. of coal per hour. 

Consumption of fuel averages 1\ lbs. of coal, or 
15 lbs. of dry pine wood for every cubic foot of 
water evaporated. 

At above rate, about fifty-two horse-power would 
consume in an ordinary good furnace about two 
tons of coal daily (or ten hours) and would require 
520 cubic feet or 3900 gallons of water. 
5 



5Q 



USEFUL INFORMATION. 



American Coal. 









Per cent, 
of ash. 


Theoretical value. 


COAL. 


In heat 
units. 


In pounds 
of water 










evap. 


KIND OF COAL. 


STATE. 








Bureau Co., 


Illinois. 


5.20 


13.025 


13.48 


Mercer Co., 


" 


5.60 


13.123 


13.58 


Montauk Co., 


" 


5.50 


12.659 


13.10 


Block, 


Indiana. 


2.50 


13.588 


14.38 


Caking, 
Cannel, 


" 


5.66 


14.146 


14.64 


«« 


6.00 


13.097 


13.56 


Lignite, 


Arkansas. 


5.25 


9.215 


9.54 


" 


Colorado. 


9.25 


13.562 


14.04 


" 


" 


4.50 


13.866 


14.35 


" 


Texas. 


4.50 


12.962 


13.41 


" Washington Terr. 


3.40 


11.551 


11.96 


Caking, 
Cannel, 


Kentucky. 


2.75 


14.391 


14.89 


" 


2.00 


15.198 


16.76 


" 


" 


14.80 


13.360 


13.84 


Lignite, 


" 


7.00 


9.326 


9.65 


Cumberland, 


Maryland. 


13.98 


12.226 


12.65 


Cannel, Pennsylvania. 


15.02 


13.143 


13.60 


Connellsville, 






6.50 


13.368 


13.84 


Semi -bituminous 






10.77 


13.155 


13.62 


Stone's Gas, 






5.00 


14.021 


14.51 


Youghiogheny, 






5.60 


14.265 


14.76 


Brown, 






'9.50 


12.324 


12.75 


Anthracite, 






3.49 


14.199 


14.70 








6.13 


13.535 


14.01 


" 






2.90 


14.221 


14.72 


Petroleum, 








20.746 


21.47 



The above Table of American Coal has been compiled from 
various sources. 



Furnace Efficiency. 

Every pound of fuel requires a given quantity of 
oxygen for its complete combustion, and thus a 
given quantity of air. This varies with different 
fuels, but, in every case, less air prevents complete 
combustion, and an excess of air causes ivaste of heat 



USEFUL INFORMATION. 



57 



to the amount required to heat it to the temperature 
of the escaping gas. With chimney draught the 
experiments of the United States Navy show that 
ordinary furnaces require about twice the theoret- 
ical amount of air to secure perfect combustion. 
Prof. Schwackhoffer of Vienna found in the boilers 
used in Europe an average excess of 70 per cent, of 
the total amount passing through the fire, or that 
over three times the theoretical amount was used. 
A series of analyses by Dr. Behr of the escaping 
gases from a Babcock & Wilcox boiler with a chim- 
ney draught showed an average excess of air equal 
to 48 per cent, of the whole quantity. A series of 
12 tests made by same with artificial forced draught, 
gave an average excess of only 22 per cent, of the 
whole quantity, and in a few cases none at all, with 
only traces of carbonic oxide, showing perfect com- 
bustion. Different fuels require different furnaces, 
and no one furnace or grate bar is equally good for 
all fuel. The "National Electric Furnace," how- 
ever, with artificial forced draught is equally good 
for all types of boilers and all kinds of fuel. 



Temperature of Fire. 

The following table from M. Pouillet will enable 
temperature to be judged by the appearance of 
the fire. 



APPEARANCE. 


TEMP. 
FAHR. 


APPEARANCE. 


TEMP. 
FAHH. 


Red just visible 
" dull 

" cherry dull 
full 
" " clear 


977° 
1290° 
1470° 
1650° 
1830° 


Orange deep 
" clear 
White heat 
Bright " 
Dazzling heat 


2010° 
219(P 
2370 ° 
2550° 
2730° 



58 



USEFUL INFORMATION. 



To determine Temperature by Fusion of 
Metals, etc. 



SUBSTANCE. 


TEMP. 
FAHK. 


METAL. 


TEMP. 
FAHK. 


METAL. 


TEMP. 
FAI1R. 


Tallow 
Spermaceti 
Wax. White 
Sulphur 
Tin 


92° 
120° 
154° 
239 : 
455° 


Bismuth 
Lead 
Zinc • 
Antimony 
Brass 


518° 
630 ° 
793 r 
810° 
1650 ° 


Silver pure 
Gold Coin 
Iron Cast med. 
Steel 
Wrought Iron 


1830° 

2156 ° 
2010° 
2550° 
2910° 



Table of Relative Value of Non-Conductors from 
Experiments by Chas. E. Emery, Ph. D. 



NON-CONDUCTOR. 


VALUE. 


NON-CONDUCTOR. 


VALUE. 


Wool Felt 


1.000 


Loam dry and open 


.550 


Mineral Wool No. 2 


.832 


Slacked Lime 


.480 


Do. with Tar 


.715 


Gashouse Carbon 


.470 


Sawdust 


.680 


Asbestos 


.363 


Mineral Wool No. 1 


.676 


Coal Ashes 


.345 


Charcoal 


.632 


Coke in lumps 


.277 


Pinewood across Fibre 


.553 


Air Space undivided 


.136 



"Mineral Wool," a fibrous material made from blastfurnace 
slag, is a good protection, and is incombustible. 



Firing of Sawdust and Shavings. 

For the last twelve years or more, the writer had, 
as a manufacturer and steam user, adopted the 
mode of forcing- the shavings from the woodworking 
surfacers into the furnace. The boiler used was of 
about 60 horse-power. The air was forced into the 
furnace with the planer shavings at a velocity of 
about 12 feet per second and at an average tempera- 
ture of about 60° Fahr. The shavings were forced 
through a pipe 12 inches in diameter, above grate. 
into the combustion chamber. The pipe had a blast 
gate to regulate the air enough in order to maintain 



USEFUL INFORMATION. 59 

a pressure in the furnace, which a little more than 
balanced the ascending gases in the funnel or ckim- 
ney. When the surfacers were in operation and 
the planer shavings forced into the furnace, the 
heating space was filled with flame to the rear end, 
and thence through the flues of the boiler, water 
being evaporated during the time very rapidly. All 
that the fireman had to do was to keep the furnace 
doors closed and watch the water in the gauges of 
his boiler. The combustion in the furnace was 
complete, as no smoke was visible. The shavings 
were forced into the combustion chamber in a 
spray-like manner, and were caught into a blaze 
the moment they entered. The oxygen of the air 
so forced into the furnace along with the shavings 
gave full support to the combustion. The amount 
of shavings consumed by being thus forced into 
the furnace was about fifty per cent, less than the 
amount consumed, when the fireman had to throw 
them in with his shovel. The air entering through 
the open doors cools down the interior, and it is 
quite clear, that the heat of the fire can not be So 
intense, when the doors are open and fresh shavings 
thrown on top of the burning stuff, something that 
has to be done very frequently. Besides, the fire- 
man, in most cases, throws into the furnace as many 
shavings as he can get in above grate. The result 
is that the necessary air can not pass through the 
mass of burning stuff, and it will thus be seen that 
nearly half is wasted by smothering the mass of 
fuel. But when the shavings are forced into the 
furnace, and the doors are kept closed, and the 
heating space is all ablaze, powerful heat is given 
to the boiler. The writer found this mode of firing 
better for the boiler, securing less labor and a saving 
in fuel where there are shavings to any amount. 



60 USEFUL INFORMATION. 

Amount of Coal burned by Ocean Steamships. 

Coal is a serious item in the expense of ocean- 
going steamships in these days of fast ships and 
quick passages. Two thousand dollars per day 
spent for fuel, is a sum exceeded by several of the 
swift transatlantic ships. It may be observed from 
the table following, what the actual average cost of 
fuel alone is for the largest vessels : 



COAL CONSUMED PER DAY. AVERAGE KNOTS 
TONS. PER HOCR. 



COST OF COAL 
PER VOYAGE. 



!~t 9 o 


S18.872 


16 


17.024 


16 A 


15.168 


1<3 t 5 o 


11.956 


16 tV 


11.056 


1'tV 


10.192 


16A 


6.440 



Oregon 337 

Citvof Rome 304 

Alaska 253 

Servia 214 

Aurania 214 

America 182 

Austral 115 

The round trip expenses run from 840,000 to 870.000. 

9 "What an enormous waste in fuel must be taking 
place in the above cases ! The amount of coal 
burned, as stated above, by the steamship Oregon, 
under skillful management, is 337 tons per day. 
xSow if once and a half of the theoretical amount of 
atmospheric air used in combustion is 225 cubic 
feet, a volume equal to 18 pounds of air to every 
pound of coal, or 450,000 cubic feet of air to a ton 
of coal, 337 tons would require 151,650,000 cubic 
feet of atmospheric air. Of this vast volume, 
oxygen, which is the only combustible element in 
it,* constitutes but one fifth, while the nitrogen, 
representing four fifths of the entire volume, is not 
only quite useless in combustion, but even retards 
it, and absorbs a large proportion of the heat of 
the fire. If we imagine the 151,650,000 cubic feet 



USEFUL INFORMATION. 61 

of air made into a long stream of one square foot 
in area, the total length will be 28,722 miles. Of 
this vast stream 22,978 miles are useless nitrogen 
passing into the furnace cold and out of it hot. 

Boiler Explosion. 

(Abstract from the Works of John Bourne, C. E.) 

There are many causes of boiler explosions. 

The chief cause of boiler explosions is, undoubt- 
edly, too great a pressure of steam, or an insuffi- 
cient strength of boiler, generally resulting from 
oxidation ; but many explosions have also arisen 
from the flues having been suffered to become red 
hot. If the safety valve of a boiler be accidentally 
jammed, or if the plates or stays be much worn by 
corrosion, while a high pressure of steam is never- 
theless maintained, the boiler necessarily bursts ; 
and if, from an insufficiency of water in the boiler, 
or from any other cause, the flues become highly 
heated, they may be forced down by. the pressure 
of the steam, and a partial explosion may be the re- 
sult. The worst explosion is where the shell of the 
boiler bursts ; but the collapse of a furnace or flue 
is also very disastrous, generally to the persons in 
the engine room ; and sometimes the shell bursts and 
the flues collapse at the same time ; for if the flues 
get red hot, and water be thrown upon them either 
by the feed pump or otherwise, the generation of 
steam may be too rapid for the safety valve to per- 
mit its escape with sufficient facility, and the shell 
of the boiler may, in consequence, be rent asunder. 
Sometimes the iron of the flues becomes highly 
heated in consequence of the improper configura- 
tion of the parts, which, by retaining the steam in 
contact with the metal, prevents the access of the 



62 USEFUL INFORMATION. 

water. The bottoms of large flues, upon which 
the flames beat down, are very liable to injur j^ from 
this cause ; and the iron of the flues thus acted 
upon may be so softened that the flues will collapse 
upwards with the pressure of the steam. It is 
found that a sudden disengagement of steam does 
not immediately follow the contact of water with 
the hot metal, for water thrown upon red hot iron 
is not immediately converted into steam, but as- 
sumes the spheroidal form and rolls about in glob- 
ules over the surface. These globules, however 
high the temperature of the metal may be on which 
they are placed, never rise above the temperature 
of 205°, and give off but very little steam; but if 
the temperature of the metal be lowered, the water 
ceases to retain the spheroidal form, and comes 
into intimate contact with the metal, whereby a 
rapid disengagement of steam takes place. 

One useful precaution against the explosion of 
boilers from too great, an internal pressure, consists 
in the application of a steam gauge to each boiler, 
which will make the existence of any undue pressure 
in any of the boilers immediately visible ; and every 
boiler should have a safety valve of its own, the 
passage leading to which should have no connection 
with the passage leading to any of the stop valves 
used to cut off the connection between the boilers, 
so that the action of the safety valve may be made 
independent of the action of the stop valve. In some 
cases stop valves have jammed, or have been carried 
from their seats into the mouth of the pipe commu- 
nicating between them, or have not been opened, 
and the action of the safet} r valves should be ren- 
dered independent of all such accidents. Safety 
valves themselves sometimes stick fast from» corro- 
sion, from the spindles becoming bent, from a 



USEFUL INFORMATION. 



63 



distortion of the boiler top with a high pressure, in 
consequence of which the spindles become jammed 
in the guides, from a larger expansion of the brass 
seat than of the cast iron socket in which it is set, 
and from various other causes which it would be 
tedious to enumerate. 



Proportions, Heating Surface, and Horse -Power 
of Boilers Fitted with Six Inch Flues. 





BOILER SHELL. 


NUMBER 


HEATING SUR- 


HORSE -POWER 






FACE, % SHELL, 
AND WHOLE 


AT 12 FEET. 






OF 




DIAMETER. 


LENGTH. 


FLUES. 


OF FLUES. 




Inches. 


Feet. 




Square Ft. 


16.7 


42 


12 


6 


201 


19.6 




14 


6 


235 


22.3 




16 


6 


268 


25.2 




18 


6 


302 


28.0 




20 


6 


336 


21.8 


44 


12 


9 


262 


25.5 




14 


9 


306 


29.1 




16 


9 


349 


32.7 




18 


9 


392 


36.4 




20 


9 


437 


23.8 


46 


12 


10 


285 


27.7 




14 


10 


.332 


31.6 




16 


10 


379 


35.7 




18 


10 


428 


39.6 




20 


10 


475 


27.3 


48 


12 


12 


327 


31.2 




14 


12 


381 


36.3 




16 


12 


436 


40.8 




18 


12 


490 


45.4 




20 


12 


545 


50.0 




22 


12 


(300 


36.7 


54 


14 


. 14 


440 


41.9 




16 


14 


503 


47.2 




18 


14 


566 


52.3 




20 


14 


628 


45.3 


60 


14 


18 


543 


51.7 




16 


18 


620 


58.1 




18 


18 


'697 


64.5 




20 


18 


774 


82-7 


66 


20 


24 


992 



64 



USEFUL INFORMATION. 



Proportions, Heating Surface, and Horse -Power 
of Boilers Fitted with Fonr Inch Tubes. 





BOILER SHELL. 


NUMBER 


HEATING SUR- 


HORSE -POWER 






FACE, % SHELL, 
AND WHOLE 


AT 15 FEET. 






OF 




DIAMETER. 


LENGTH. 


TUBES. 


OF TUBES. 




Inches. 


Feet. 




Square Ft. 


28.5 


48 


12 


26 


428 


33.2 




14 


26 


498 


38.0 




16 


26 


570 


42.7 




18 


26 


641 


47.5 




20 


26 


713 


32.1 


50 


12 


30 


482 


37.5 




14 


30 


562 


42.9 




16 


30 


643 


48.1 




18 


30 


722 


53.5 




20 


30 


803 


34.1 


52 


12 


32 


511 


39.7 




14 


32 


596 


45.4 




16 


32 


681 


51.1 




18 


32 


766 


56.8 




20 


32 


852 


37.7 


54 


12 


36 


565 


44.0 




14 


36 


660 


50.3 




16 


36 


754 


56.6 




18 


36 


849 


62.8 




20 


36 


942 


42,1 


56 


12 


41 


632 


49.2 




14 


41 


738 


56.2 




16 


41 


843 


63.3 




18 


41 


949 


70.3 




20 


41 


1054 


45.7 


58 


12 


45 


686 


53.5 




14 


45 


802 


61.1 




16 


45 


916 


68.7 




18 


45 


1030 


76.3 




20 


45 


1144 


46.9 


60 


12 


46 


704 


54.7 




14 


46 


821 


62.6 




16 


46 


939 


70.3 




18 


46 


1055 


78.1 




20 


46 


1172 


94.0 


66 


20 


56 


1410 



USEFUL INFORMATION. 65 

The Prevention of Scale in Steam Boilers. 

(From the Scientific American Suppl.) 

The formation and prevention of scale in steam 
boilers has been, from time to time, discussed 
pretty keenly in almost every mechanical and en- 
gineering journal. The number of specifics and 
nostrums, sold under all kinds of fancy names, for 
its prevention and removal are legion. Complicated 
apparatuses and constructions have also been pro- 
posed, and, to some extent, used for removing the 
scale by boiling and heating the feed-water under 
pressure previous to use. Unfortunately, how- 
ever, the trouble and expense of these arrange- 
ments, added to their first cost, come to nearly the 
same thing as simply replacing the worn out steam 
boiler, which has become injured by scale, with a 
new one. 

Learned articles with chemical signs and equiv- 
alents have been published, explaining scientifically 
the theory and formation of boiler scale ; but to 
many steam users unacquainted with chemistry, 
they are about as instructive as if they were written 
in a foreign language. Perhaps it may not, there- 
fore, be out of place to explain, in as simple a manner 
as possible, the nature of boiler-scale and the cause 
of its formation. What is termed boiler-scale is 
a mineral deposit from the feed-water, whenever 
hard water is used as a source of supply. All lake, 
river, and spring water is more or less hard. The 
hardness is caused by the water coming in contact 
with certain mineral substances which the water 
dissolves to a small extent when running over or 
through the ground. These substances are chiefly 
carbonates and sulphates of lime, some magnesia, 



6b USEFUL INFORMATION. 

and at times, traces of iron. There are two kinds 
of hard water, which chemists call "temporary" 
and "permanent" hard water. The first kind, or 
temporary hardness, is caused by the carbonate of 
lime and magnesia which has been dissolved by the 
water, and it is called temporarily hard because, 
when the water is boiled, all the carbonate of lime 
is rendered insoluble, that is to say, it is no longer 
dissolved by the water, but is thrown out, and falls 
in a white, slimy deposit of carbonate of lime. 

The second kind of hard water, that termed per- 
manently hard, is caused by the sulphate of lime 
dissolved by the water. Simple boiling does not 
make it insoluble or remove it. The water, there- 
fore, that contains it, is permanently hard, that is 
to say, it can not be softened by simple boiling, 
but only by boiling under a high pressure, or by 
heating the water up to a high temperature, which 
means the same thing. 

All water contains more or less of these two sub- 
stances, carbonate and sulphate of lime, causing 
the temporary and permanent hardness. They are 
by no means always present in the same quantities 
or proportions, that is to say, some waters are 
much harder than others, and some are much more 
temporarily hard than permanently hard, or the 
reverse may be the case. 

It will be seen, therefore, from this simple ex- 
planation that the carbonate and sulphate of lime 
must both be rendered insoluble and deposited in 
the steam boiler, the first as soon as the water be- 
gins to boil, the second as soon as the water comes 
under the steam- pressure of the boiler.* It will 
also be evident that they will be deposited in the 
hottest place in the steam boiler, that is to say, 
just on the surface of the plates exposed to the fire, 



USEFUL INFORMATION. 67 

it being entirely the action of the heat that makes 
them insoluble. This is, of course, what takes place 
in practice. The coolest water in the boiler is con- 
stantly descending, the hot water ascending. The 
cold water is deprived of its lime salts just on the 
surface of the heated plate ; the purified water 
passes up, bearing the sulphate and carbonate of 
lime sticking to the boiler plate in the form of scale. 
The action of this scale is that of a non-conductor, 
that is to say, it keeps the heat passing into the 
iron plate from being imparted to the water of the 
boiler ; the consequence is a largely increased con- 
sumption of fuel, and the burning of the boiler- 
plate by the fire, owing to its not being in contact 
with the water, and thus kept cool. 

From the above simple description of the theory 
of the formation of boiler-scale, it will be evident 
that if the substances causing the hardness of the 
water, and also the boiler-scale, can be rendered 
insoluble before they come in contact with the 
heated boiler plate, the formation of the boiler- 
scale will be impossible. This is all that is re- 
quired, and not necessarily their removal previous 
to entering the boiler, as they settle down to the 
bottom, instead of adhering to the plates or the 
tubes, and pass away by the blow-off tap. This is, 
or rather should be, the object of the many boiler 
compounds sold as anti-crustators ; but of the many 
different kinds offered to the public, few fulfill the 
necessary conditions of doing their work cheaply 
and effectively. 

A boiler compound should, in the first place, 
render all the lime salts insoluble before they are 
rendered insoluble by coming in contact with the 
heated plates of the boiler. Secondly, it should 
have no action whatever on the iron of which the 



68 USEFUL INFORMATION. 

boiler is made; and lastly, it should be cheap, 
readily obtained, and easy to handle. 

Now, considering all these points, no substance 
seems better suited for the purpose than pure soda. 
The usual form, or what is generally understood 
by sodaj is soda ash or soda crystals. These 
articles, however, are not soda properly so called, 
but carbonate of soda more or less impure, that is 
to say, soda in combination with carbonic acid, and 
in this form sluggish and comparatively ineffective 
in rendering insoluble and removing the carbonates 
and sulphates of lime which form the boiler-scale. 
Soda properly so called is "caustic soda," that is 
to say, soda uncombined with any acid, and, there- 
fore, in a free state. This article is very effective 
in softening water, or in other words, rendering the 
carbonates and sulphates of lime insoluble, and 
when pure, has no action whatever on the boiler 
plates. When required for boiler purposes it should 
always, therefore, be used in a pure state, say not 
less than a strength of 98 per cent. , the total impur- 
ities, therefore, not exceeding 2 per cent. Common 
caustic soda, as sold in drums containing large solid 
blocks, does not do well for boiler purposes ; the 
usual strength of this article is only 60 per cent., 
and it contains sulphur salts, besides a large quan- 
tity of common salt, which acts very prejudiciousty 
on the boiler plates. The pure 98 per cent, caustic 
soda is prepared in a powdered form by some man- 
ufacturers ; and one of them, the Greenbank Alkali 
Co., of St. Helen's, England, seems to have made 
a specialty of it in small, air-tight 10 lb. canisters, 
which are very convenient for small consumers. 
With the powdered caustic soda there is no trouble 
in handling or weighing out the exact quantity re- 
quired, as is the case with the large solid blocks in 



USEFUL INFORMATION. 69 

drums, and it also dissolves instantly in cold water. 
In using pure, powdered caustic soda for boiler 
purposes, all that is necessary is to put a small 
quantity daily into the feed-water of the boiler. In 
this way the lime is all rendered insoluble, forms 
no scale, and passes off in the blow-off as a muddy 
sediment. 

The quantity required is quite small, as a very 
little really pure caustic soda goes a long way. In 
ordinary cases about 3 lbs. added daily to the feed- 
water of a 20 horse-power boiler will keep it perfectly 
clean and free from scale. For large consumers, with 
many boilers, a more accurate estimation of the quan- 
tity required to soften the water will be necessary. 

It has been already mentioned that ordinary 
water is of varying degrees of hardness and com- 
position, but if drawn from the same source it is 
generally fairly uniform. The very hardest water 
generally met with will be softened and the lime re- 
moved by adding one-quarter of an ounce of pure, 
powdered 98 per cent, caustic soda to each gallon 
of water. 

In most cases one-eighth part of an ounce is suffi- 
cient, and where the water is fairly good, one- 
sixteenth part of an ounce to the gallon of water 
will prevent all scale. To ascertain the quantity 
necessary, add one-sixteenth part of an ounce of 
98 per cent, powdered caustic soda to a gallon of 
water and boil it, as this causes the lime sediment 
quickly to settle. Pour off the clear water and add 
to it another sixteenth part of an ounce of powdered 
caustic soda ; if the water remains clear, the first 
addition of soda is sufficient to remove the lime 
salts. If it become muddy, the second quantity 
added is necessary. In this way a sufficiently ac- 
curate estimation of the quantity of pure powdered 



70 USEFUL INFORMATION. 

caustic soda required can be made, and then added 
to the feed-water in the same porportion. For 
example, suppose one-sixteenth part of an ounce 
per gallon was necessary. This will be just about 
four pounds of powdered 98 per cent, caustic soda to 
the thousand gallons ; and, as the cost of really pure 
powdered soda is about two pence per pound, the 
cost of perfectly softening the water will be eight 
pence per thousand gallons — a small cost compared 
with the advantage obtained of having no boiler-scale. 

If the quantity of water used in the steam boiler 
can not be easily ascertained, and the water is to be 
softened by adding Greenbank's 98 per cent, pow- 
dered caustic soda, per 1000 gallons, used as given 
in the previous directions, the requisite quantity 
can be arrived at in the following manner : 

Good Water. — One pound of Greenbank's 98 
per cent, powdered caustic soda for each ton of 
coal burnt. 

Medium Water. — Two pounds of Greenbank's 
98 per cent, powdered caustic soda for each ton of 
coal burnt. 

Hard Water. — Three pounds of Greenbank's 
98 per cent, powdered caustic soda for each ton of 
coal burnt. 

The Greenbank powdered caustic soda should be 
put daily into the feed water in the above propor- 
tions, and the blow-off tap used rather more fre- 
quently. All scale will in this manner be pre- 
vented. The Greenbank Double Concentrated 98 
per cent. Powdered Caustic Soda being pure, has 
no action whatever on the boiler plates or fittings. 

This is not the case with the ordinary caustic 
soda, owing to the impurities it contains, and which 
frequently has caused it to be justly condemned as 
a boiler anti-crustator. 



USEFUL INFORMATION. 71 

Instructions to Engineers. 

Rules for engineers and firemen for the manage- 
ment and care of steam boilers in getting up steam. 
— Before lighting the fire in the morning, raise your 
safety valve, and ascertain how many gauges of 
water there are in your boiler. Never unbank or 
replenish the fires until this is done. Accidents 
have occurred, and many boilers have been entirely 
ruined from neglect of this precaution. To guard 
against loss by leakage and evaporation, leave the 
water up to the third gauge at night and keep it up 
to the second gauge during working hours. Clean 
all ashes and cinders from the furnace and ash-pit, 
and spread a layer of two or three inches of coal 
over the grate bars ; pile on plenty shavings over 
the coal, with dry sawdust, and split wood, etc., 
then start your fire. Keep the fire even and regu- 
lar over the grate bars, about five inches thick with 
soft coal, and about three inches with anthracite, 
and always avoid excessive firing. Moderate charges, 
or firings, at intervals of 15 or 20 minutes, give the 
best result. In getting up steam from cold water, 
the fire should be raised gradually, to avoid damag- 
ing the boiler by unequal expansion of the iron. 
If steam commences to blow off at the safety valve, 
while the engine is at rest, start your pump or in- 
jector to create a circulation, cover or bank yowc 
fire with a charge of ashes or fresh coal to absorb 
the heat, and allow the steam to have free egress 
through the safety valve. If by neglect the water 
gets very low, and the boiler dangerously hot, the 
fire should either be drawn, or drenched with water. 
Should the fire be very hot, and the water supply 
temporarily cut off, stop the engine and cover the 
fire quite thickly with fresh fuel to absorb the heat, 
6 f 



72 USEFUL INFORMATION. 

keeping the usual allowance of water in the boiler 
until the supply is renewed. Boilers should be 
blown out every 2 or 3 weeks, or as often as mud 
appears in the water, but never until after the fire 
has been drawn at least one hour, and the damper 
closed, otherwise the empty boiler might be dam- 
aged by the heat. Never fill a hot boiler with cold 
water, as the sudden contraction many times re- 
peated will eventually cause it to leak. Never blow 
out a boiler with a higher pressure than 50 lbs. to 
the square inch, as steam at a high pressure indi- 
cates a high temperature in the iron, which under 
careful management should always be let down 
gradually. Previous to filling a boiler, raise the 
valve to permit the free egress of air which might 
otherwise do manifold damage. Use every possible 
precaution against foul water, as it induces foaming 
in the boiler ; soapy or oily substances and insuf- 
ficiency of steam room have a like effect, causing 
a boiler to burn on the spots where the water is 
lifted from it, and the glass gauges to indicate 
falsely. 

Keep gauge cocks clear and in constant use; 
glass gauges should not be relied on altogether. 

. Particular care should be taken to keep sheets 
and parts of boiler exposed to the fire perfectly 
clean. 

Under all circumstances keep the gauges, 
cocks, etc., clean and in good order, and things 
generally in and about the engine and boiler room 
in a neat condition. 

Keep a sharp lookout for leaks, and repair them 
if possible without delay, and allow no water to 
come in contact with the exterior of the boiler 
under any circumstances. Examine and repair 
every blister as soon as it appears, and make fre- 



USEFUL INFORMATION. 73 

quent and thorough examination of the boiler with 
a small steel hammer. 

In case of foaming, close the throttle, and keep 
it closed long enough to show true level of water. 
If the water level is right, feeding and blowing will 
generally stop the trouble. With muddy water it 
is a safe rule to blow out 6 or 8 inches every day. 
If foaming is violent from dirty water, or change 
from salt to fresh, or from fresh to salt, in addition 
to following the above directions, check draught, 
and cover the fire with ashes or fresh fuel. 

Great watchfulness is necessary, when steam is 
raised, the safety valve fixed, the fire strong, and 
the engine at rest. In every case there is a rapid 
and dangerous absorption of heat, the temperature, 
latent and sensible heat included, often rising to 
1200° Fahrenheit. 

Frequently it is but the work of an instant to 
convert the latent into sensible heat, thus genera- 
ting an irresistible force which bursts the boiler and 
destroys life and property. The destruction gener- 
ally takes place at the moment of starting the en- 
gine, the opening of the valve inducing a commo- 
tion in the water, which flashes into steam the in- 
stant it strikes the heated plates. Steam has been 
known to rise from a pressure of 32 lbs. to the 
square inch to 90 lbs. to the square inch, in the 
short space of seven minutes, with the engine at 
rest. It ought to quicken the vigilance of every 
engineer to know that the explosive energy in each 
and every cubic foot of water in his boiler at 60 lbs. 
pressure, is equal to that contained in 1 lb. gun- 
powder. 

Before starting the engine, warm the cylinder by 
admitting steam so as to slowly move the piston 
back and forth, letting the condensed water flow 



74 USEFUL INFORMATION.' 

from the drip-cocks, which should be left open all 
night for this purpose ; especially should this be 
done during cold and frosty weather, during which 
time all pipes and connections should have extra 
protection. 

The minimum speed of the piston should be 240 
feet per minute, and the maximum speed 700 feet 
in any engine. 



Employ Qualified Engineers. 

From avaricious motives ' it has become quite 
common to discharge or to decline to employ quali- 
fied and careful engineers. 

Incompetent men are employed, because their 
labor costs a few dollars less than that of the 
former. This is • too much of a bad thing to pass 
over without notice. Employ good skillful men in 
the management of steam power, and pay them 
decent wages or employ none at all. 

If an oversight takes place, and the best and 
most careful men are liable to make mistakes, 
never scold, reprimand, or exact service during 
dangerous emergencies, as in the event of lost 
water in the boiler. In no case risk life, limb, or 
property, and do not let the consideration of sav- 
ing a few dollars debar you from securing intelli- 
gent assistants. 

The Turkish mode of driving business on a late 
occasion was to discharge the English engineers 
who brought the war vessels which were built in 
England, and supply the vacancies by installing 
cheap green hands. After getting up steam the new 
" Chief" proceeded to start the engines. A lift at 
a crank produced no results, a pull at a lever was 



USEFUL INFORMATION. 75 

equally useless. At length the illustrious official 
espied a bright brass cock, and thinking he had got 
hold of a sure thing this time, proceeded to give it 
a twist, when he was suddenly saluted with a jet of 
steam full in the face, which swept the "engineer" 
and his assistants out of the engine room, into the 
fire room down stairs. — So much for cheap labor 
and the consequent results. — M. A. Guide. 



New Boilers and Engines. 

In starting new machinery for the first time, the 
greatest care should be taken, in order to prevent 
injury. The change from low temperature to*very 
high ones exerts tremendous force, which is all the 
more dangerous and insidious for the reason that 
its effects are not seen until the mischief is done. 
This great force is expansion, or the dilation of 
volume — bulk, or superfices, by heat, and those un- 
familiar with it, have no conception of the strains 
set up. We shall not go into a discussion of them 
in this article, for it would require many figures and 
references to authorities and physics for which the 
general reader has little interest. We content our- 
selves with brief practical directions for avoiding 
damage to plant, involving future repair and pecun- 
iary loss. 

Boilers newly set should be heated very slowly 
indeed, and the fires should not be lighted under 
the boilers for at least two weeks after setting, if it 
is possible to wait this length of time. These two 
weeks enable all parts of the mason work to set 
gradually and harden naturally ; the walls will be 
much more likely to remain perfect, than where 
fires are lighted, while the mortar is yet green. 



76 USEFUL EsTORMATIOy. 

When a fire is started under a new boiler for 
the first time, it should be a very small one. and no 
attempt should be made to do more than moderately- 
warm all parts of the brick work. A slow fire should 
be kept up for twenty-four hours, and on the second 
day it may be slightly increased. Three full days 
should elapse before the boiler is allowed to make 
any steam at all. 

When the pressure rises it should not be allowed 
to go above four or five pounds by the gauge, and 
the safety valve weight should be taken off to pre- 
vent any possibility of increase. Steam should be 
allowed to go through all the pipes attached for 
steam, and blow through the engine before any 
attempt is made to get pressure on them. The 
object of all these precautions and this care is to 
prevent injury by sudden expansion, which, as we 
have already stated, may cause great damage. The 
cylinder itself should be thoroughly heated before 
the engine is started, and the back head should be 
left off and steam blown through the port by moving 
the valve by hand. This will drive out any borings 
or chips and core sand left in the parts. If these 
precautions are observed, and the engine run very 
slowly indeed, at first, for a few hours, increasing 
the speed by degrees, the probabilities are that much 
fewer repairs will be needed than where reckless 
haste is used to start up at once after the last joint 
has been made on the premises. — Milling Engineer. 

Practical Remarks on Combustion and Firing of 

Steam Boilers. 

Carbon is the chief constituent of anthracite and 
bituminous coals. Anthracite contains only about 
4 per cent, of hydrogen, and when burning produces 



USEFUL INFORMATION. 77 

bat little flame or smoke. Bituminous coal contains 
more hydrogen, and it is this gas which produces 
flame during its combustion. Bituminous coal being 
a combination of hydrogen and carbon, when in its 
natural state, is classed with hydrocarbons, whereas, 
hard coal is considered as almost pure carbon ; 
chemically it is an impure sub-variety of it. Gas- 
coke resembles anthracite, minus its small amount 
of volatile gases. 

The solid and liquid fuels which the bowels of the 
earth contain, were probably formed at a very early 
period, as their presence has been known for cent- 
uries. When anthracite was first discovered, it was 
thought to be a useless substance of no commercial 
value. The heat value of a pound of Pennsylvania 
anthracite is about 14,198 units; by some it is 
given as 14,500. There is a lignite coal mined in 
Kentucky and Arkansas, the heat value of which 
is not above 9300, while the heat value of dry 
wood is not above 5600. The object of this article 
is not to dilate on the value of different kinds of 
fuel, but rather, to draw attention to the combus- 
tion of it. 

In the furnace much of the gaseous portion of the 
fuel is lost by improper handling of the fires, and 
by too much or too little air being admitted through 
or above the grate bars. 

Some have been led to believe that it is advanta- 
geous to wet bituminous coal preparatory to putting 
it upon the fire, but there can be no economy in 
burning wet fuel of any kind, for much of the avail- 
able heat of the fuel is rendered latent in the steam 
and other vapors liberated from the wet fuel by the 
heat of the furnace, and the heat so absorbed is 
given out again only after the gases are condensed 
outside, or within the chimney. 



78 USEFUL INFORMATION. 

When a furnace is first charged with wet tan or 
green wood, we observe dense clouds of smoke and 
steam escaping from the chimney- top, and after a 
few hours' run, if we should then examine the flues 
or tubes, would find them coated with soot, which is 
a sure indication of imperfect combustion. I do 
not mean by this that the absence of smoke in- 
dicates that a furnace is consuming its own gases, 
for the waste of heat is sometimes enormous when 
no smoke is visible. For instance : I partly open 
the furnace doors soon after charging the furnace 
with fresh fuel. No vestige of smoke can be seen, 
but we know that the excess of air rushing in 
through the open doors, is cooling down and con- 
densing the gases as they rise from the burning 
fuel, and carrying them off at a comparatively low 
temperature. Anthracite dust is unfit to burn dry, 
unless mixed with bituminous coal. The dust, 
when used alone, closes the air inlets through the 
grate-bars, cuts off the supply of oxygen necessary 
for combustion, and smothers the fire. Anthracite 
dust lies heavily on the grate-bars, like so much 
red hot sand, and if we disturb it with the fire tools, 
a large amount of the half-burnt fuel falls through 
the grate-bars into the ash-pit. — M. Eng. 



Coal Tar Product. 

One ton of ordinary gas coal will produce 10.008 
cubic feet of gas, 20 or 30 gallons of Ammonia 
water — say 30 — , 12 gallons or 140 lbs. of coal tar, 
and about three quarters of a ton of coke. 



USEFUL INFORMATION. 79 



Valuable Information for Business Men. 

Demand Notes are payable on presentation, with- 
out grace, and bear legal interest after a demand 
has been made, if not so written. An endorser on 
a demand note is holden only for a limited time 
variable. in different states. 

A Negotiable Note must be made payable either 
to bearer, or be properly endorsed by the person to 
whose order it is made. If the endorser wishes to 
avoid responsibility, he can endorse "without re- 
course." 

A Joint Note is one signed by two or more per- 
sons, who can each become liable for the whole 
amount. 

Tliree Days' Grace are allowed on all time notes, 
after the time for payment expires; if not then 
paid, the endorser, if any, should be legally noti- 
fied, to be holden. 

Notes Falling Due Sunday, or on a legal holiday y 
must be paid the day previous. 

Notes dated Sunday are void. 

Altering a Note in any manner, by the holder, 
makes it void. 

Notes given by Minors are void. 

Hie Maker of a Note that is lost or stolen is not 
released from payment if the amount and considera- 
tion can be proven. 

Notes Obtained by Fraud or given by intoxicated 
persons, can not be collected. 

An Endorser has a right of action against all 
whose names were previously on a note endorsed 
by him. 



80 USEFUL INFORMATION. 

One Dollar Loaned 100 Years at Compound Interest 
would amount to the following Sum : 

1 per cent. S 2.75 

3 " 19.25 

6 " 340.00 

10 " 13,809.00 



12 per cent. S 84.675.00 

15 " 1,171,405.00 

18 " 15,145.207.00 

24 " 2,551,799,404.00 



Greatest known Depth of the Ocean. 

The greatest depth which has been ascertained 
by sounding, is five miles and a quarter (25.720 
feet or 4.620 fathoms), not quite equal to the height 
of the highest known mountain, Mount Everest, 
which measures 29,002 feet or b\ miles in height. 
The average depth between 60 degrees north and 
60 degrees south, is nearly three miles. 

First Steamboat and Locomotive in the U. S. 

The first steamboat plied the Hudson in 1807. 
The first use of a locomotive in the United States 
was in 1829. 

Long Measure— Distance. 

3 barley corns 1 inch, 12 inches 1 foot, 3 feet 
1 yard, 5^ yards 1 rod, 40 rods 1 furlong, 8 furlongs 
1 mile. 

Lightning Rods. 

The golden rule of safety is to provide the build- 
ing with plenty of rods or conductors, and make 
sure that their lower ends, in the ground, are sol- 
dered to a large surface of metal or other conduct- 
ing material placed underground. The common 
method is simply to stick the end of the rod three 



USEFUL INFORMATION. 81 

feet down into dry earth. But this is unsafe, be- 
cause dry earth is a very poor conductor of elec- 
tricity. To compensate for this lack of conductiv- 
ity, the bottom of the rod should communicate 
with a large extent of conducting material. This 
may be done by soldering the lower end of the 
rod to water or gas pipes, if they exist; if not, 
then dig a trench four feet deep, six inches wide 
at bottom, in which deposit a layer six inches 
thick of coal dust, charcoal, anthracite, or bitumi- 
nous coal. Bed the end of the rod for several feet 
in this layer of coal, which is a pretty good con- 
ductor of electricity. The trench should be one 
hundred or more feet in length. The rods should 
be placed on all ridges, corners, and chimneys. All 
metallic roofs, gutters, and water-pipes should'have 
soldered connection with the rod, which should not 
be insulated from the building. All metallic water, 
gas, stove, and other pipes within the building, all 
bell wires, masses of metal, machinery, should be 
connected with the ground, in the manner described 
for the rods. The more conductors that are con- 
nected with the ground in this way, the greater the 
safety. 

Common one-half inch square iron makes a good 
conductor. So does copper wire one eighth inch in 
diameter. 

Scraps of Information. 

1. The light from the sun occupies 8 J minutes in 
traveling the earth, the distance being ninety-two 
millions of miles. The light of the fixed star 
"Sirius," supposed to be the nearest of the stars, 
is 3 J years in reaching the earth, the distance being 
over twenty millions of miles. 



82 USEFUL INFORMATION. 

2. The intensity of illumination on a given sur- 
face is inversely as the square of its distance from 
the source of light. If the page of a book held 
twelve inches from a candle be moved six inches 
nearer, the light on the page 'is 'made four times 
stronger. 

3. Doubling the diameter of a pipe increases its 
capacity four times. Friction of liquids in pipes in- 
creases as the square of the velocity. In calculating 
horse-power of Tubular or Flue boilers consider 
16 square feet of heating surface equivalent to one 
nominal horse-power. 

4. Steam is a perfect gas and follows the laws 
governing such fluids. It is stated that steam super- 
heated in an independent vessel increases in press- 
ure for every degree of increase in temperature. 
Also, that steam can not be superheated in the 
vessel in which it is generated. We respectfully 
dissent from both of these propositions ; broadly 
upon the ground that it is a poor conductor of heat, 
and therefore, through want of circulation, various 
temperatures may exist in the same vessel. 

Saturated steam of thirty pounds per square inch 
may increase in pressure when heated higher than 
its normal temperature, but dry steam will, we 
think, be an exception. — M. Eng. 

Capacity of Cisterns for Each Ten Inches 
in Depth. 

Twenty-five feet in diameter hold 3059 gallons. 
Twenty feet in diameter hold 1958 gallons. 
Fifteen feet in diameter hold 1101 gallons. 
Fourteen feet in diameter hold 959 gallons. 
Thirteen feet in diameter hold 827 gallons. 
Twelve feet in diameter hold 705 gallons. 



USEFUL INFORMATION. 



83 



Eleven feet in diameter hold 592 gallons. 

Ten feet in diameter hold 489 gallons. 

Nine feet in diameter hold 396 gallons. 

Eight feet in diameter hold 313 gallons. 

Seven feet in diameter hold 239 gallons. 

Six and one half feet in diameter hold 206 gallons. 

Six feet in diameter hold 176 gallons. 

Five feet in diameter hold 122 gallons. 

Four and one half feet in diameter hold 99 gallons. 

Four feet in diameter hold 78 gallons. 

Three feet in diameter hold 44 gallons. 

Two and one half feet in diameter hold 30 gallons. 

Two feet in diameter hold 19 gallons. 

Velocity and Force of the Wind. 



DESCRIPTION 
OF THE WIND. 



MILES 


FEET 


PER 


PER 


HOUR. 


MINUTE. 


1 


88 


2 


176 


3 


264 


4 


352 


5 


440 


6 


528 


8 


704 


10 


880 


15 


1320 


20 


1760 • 


25 


2200 


30 


2640 


35 


3080 


40 


3520 


45 


3960 


50 


4400 


60 


5280 


80 


7040 


100 


8800 



PRESSURE ON A 

SQUARE FOOT 

IN POUNDS. 



Barely observable 

Just perceptible •< 

Light breeze 

Gentle pleasant wind-! 

Fresh breeze 

Brisk blow 

Stiff breeze .... 

Very brisk 

High wind ; 

Very high wind 

Gale 

Storm 

Great storm 

Hurricane 

Tornado 



.005 
.02 
.045 
.08 
.125 
.18 
.32 
.5 
1.125 
2. 

3.125 
4.5 
6.125 
8. 

10.125 
12.5 
18. 
32. 
50. 



84 USEFUL INFORMATION. 

Distinguished American Inventors. 

Benjamin Franklin; b. Boston, 1706 ; d. 1790 ; 
inventor of the lightning-rod. 

EH Whitney; b. Westborough, Mass., 1765; 
d. 1825 ; inventor of the cotton gin. 

Robert Fulton; b. Little Britain, Pa., 1765; 
d. 1825 ; inventor of the steamboat. 

Jethro Wood; b. White Creek, N. Y., 1774; 
d. 1834 ; inventor of the modern cast-iron plough. 

TJwmas Blanchard; b. Sutton, Mass., 1788; 
d. 1864 ; inventor of tack machine. 

Cyrus H. McCormick; b. Walnut Grove, Va., 
1809 ; inventor of harvesting machines. 

Charles Goodyear; b. New Haven, Conn., 1800; 
inventor of the simple mixture of rubber and 
sulphur. 

Samuel F. B. Morse; b. Charlestown, Mass., 
1791 ; d. 1872 ; inventor of electric telegraph. 

Elias Hoive; b. Spencer, Mass., 1819; d. 1867 
inventor of the modern sewing machine. 

James B. Eads; b. Lawrenceburgh, Ind., 1820 
d. March 8, 1887 ; author and constructor of the 
great steel bridge over the Mississippi at St. Louis 
1876, and the jetties below New Orleans, 1876 
His remarkable energy was shown in 1861, when 
he built and delivered complete to Government, all 
within sixty-five days, seven iron-plated steamers, 
600 tons each ; subsequently, other steamers. Some 
of the most brilliant successes of the Union arms 
were due to his extraordinary rapidity in construct- 
ing these vessels. 



USEFUL INFORMATION. 85 

The Great Wonders of America. 

YosemiteValley , California ; 57 miles from Coulter- 
ville. A valley from 8 to 10 miles long, and about 
one mile wide. Has very steep slopes about 3,500 ft. 
high ; has a perpendicular precipice 3,089 ft. high ; 
a rock almost perpendicular, 3,270 ft. high; and 
waterfalls from 700 to 1000 ft. 

Niagara Falls — A sheet of water three quarters 
of a mile wide, with a fall of 175 ft. 

Natural Bridge over Cedar Creek in Virginia. 

New State Capitol at Albany, N. Y. 

Mammoth Gave in Kentucky. 

New York and Brooklyn Bridge. 

Croton Aqueduct in New York City. 

Lake Superior — The largest lake in the world. 

Washington Monument, Washington, D. C, 555 ft. 
high. 

City Park, Philadelphia, Pa. — The largest park 
in the world. 

The Central Park in New York City. 

Height of Principal Monuments and Towers. 



Names. 


Places. 


Feet. 


Pyramid of Cheops, 


Egypt, 


486. 


Antwerp Cathedral, 


Belgium, 


476. 


Strasburg Cathedral^ 


Germany, 


474. 


Pyramid of Cephrenes, 


Egypt, 


456. 


St. Peter's Church, 


Rome, 


448. 


St. Martin' s Church atLandshut 


, Germany, 


411. 


St. Paul's Church, London, 


England, 


365. 


Salisbury Cathedral, 


England, 


400. 


Cathedral at Florence, 


Italy, 


387. 


Cathedral at Cremona, 


Lombardy, 


396. 


Church at Fribourg, 


Germany, 


386. 



86 



USEFUL INFORMATION. 



Names. 
Cathedral of Seville, 
Cathedral of Milan, 
Cathedral of Utrecht, 
Pyramid of Sekkarah, 
Cathedral of Notre Darne, 
St. Mark's Church, 
Assinelli Tower, Bologna, 
Trinity Church, 
Column at Delhi, 
Porcelain Tower, Nankin, 
Church of Notre Dame, 
Bunker Hill Monument, 
Leaning Tower of Pisa, 
Washington Monument, 
Monument, Place Vendome, 
Trajan's Pillar, Rome, 
Obelisk of Luxor, now in 



Places. Feet. 

Spain, 360. 

Lombardy, 355. 

Holland, 356. 

Egypt, 356. 

Munich, Bavaria, 348. 



Venice, 


328. 


Italy, 
New York, 


272. 

284. 


Hindostan, 


262. 


China, 


260. 


Paris, 


224. 


Massachusetts, 


221. 


Italy, < 
Baltimore, 


179. 
175. 


Paris, 


153. 


Italy, 


151. 


Paris, 


110. 



Highest and Greatest Mountains in the World. 

Aetna, a volcano in Sicily, 10,900 ft. 

Antisana, Republic of Ecuador, 14,300 ft. 

Ararat, resting-place of Noah's Ark, Armenia, 
12,700 ft. 

Ben Nevis, highest in Great Britain, Scotland, 
4,400 ft. 

Black Mountains, the highest of the Blue Ridge, 
N. C, 6,500 ft. 

Broivn Mountain, highest of the Rocky Mount- 
ains, U. S., 16,000 ft. 

Chimborazo, Republic of Ecuador, 21,400 ft. 

Cotopaxi, the highest volcano, Ecuador, 18,900 ft. 

Dhawalaghiri, one of the Himalaya Mountains, 
Asia, 25,500 ft. 



USEFUL INFORMATION. 87 

Fremont's Peak, Bocky Mountains, Wyoming, 
13,575 ft. 

Geesh, highest in Africa, 15,100 ft. 

Hecla, a volcano in Iceland, 5,500 ft. 

Hindoo-Koosh, Afghanistan, 20, £94 ft. 

Jungfrau, Alps, Switzerland, 13,700 ft. 

Lebanon, Syria, 10,000 ft. 

Mansfield, highest of Green Mountains, Vermont, 
4,275 ft. 

Miltzin, highest of Atlas Mountain, Morocco, 
11,498 ft. 

Mont Blanc, Switzerland, 15,900 ft. 

Mi. Everest, Himalayas, highest in the world, 
Thibet, 29,000 ft. 

Mi. Faimveather, Alaska, 14,475 ft. 

Mt. Hood, Oregon, 11,220 ft. 

Mt. Marcy, highest in New York, 5,400 ft. 

Mt. Ramier, Washington Territory, 14,445 ft. 

Mt. Roa, highest in Oceanica, Hawaii, 17,500 ft. 

Mt. Shasta, California, 14,440 ft. 

Mt. Sinai, Arabia, 8,200 ft. 

Mt. St. Helens, Washington Territory, 13,475 ft. 

Mt. Washington, highest of White Mountains, 
N. H., 6,293 ft. 

Mt. Whitney, California, 14,885 ft. 

Olympus, Greece, 6,600 ft. 

Ophir, Sumatra, East Indies, 13,800 ft. 

Parnassus, the home of the Muses, Greece, 
6,000 ft. 

Peaks of Otte, Virginia, 4,250 ft. 

Perdu Mount, highest of the Pyrenees, France, 
11,300 ft. 

Pike's Peak, Colorado, 14,215 ft. 

Popocatapetl, highest in Mexico, 17,700 ft. 

Round Top, highest of Catskill Mountains, N. Y., 
3,800 ft. 



88 



USEFUL INFORMATION. 



Sneehatan. highest of the Doverfield Mountains, 
Norway, 8,110 ft. 

Sorata, highest in Bolivia, S. A., 25,400 ft. 

St. Bernard, Switzerland, 8,000 ft. 

St. Elias, highest in North America, Alaska, 
17,900 ft. 

Stromboli, volcano in Mediterranean Sea, 3,000 ft. 

Teneriffe, Peak of, one of the Canary Isles, 
12,000 ft. 

Vesuvius, volcano, near Naples, 3,900 ft. 



The Longest and Greatest Rivers in the World. 



Name. Miles. 

Amazon 3600 

Nile 3000 

Missouri, to its 
Junction with the 
Mississippi, . . . 2900 
Missouri, to the 
sea, the longest 
in the world, . . 4100 
Mississippi, proper 2800 

Lena 2600 

Niger, or Jobila . 2600 

Obe 2500 

St. Lawrence . . . 2200 

Madeira 2000 

Arkansas 2000 

Volga 2000 

Rio Grande .... 1800 

Danube 1600 

St. Francisco . . . 1300 
Columbia 1200 



Xame. Miles. 

Nebraska 1200 

Red River 1200 

Colorado in Cal. . 1100 
Yellow Stone . . . 1000 

Ohio 950 

Rhine 950 

Kansas 900 

Tennessee 800 

Red River of the 

North 700 

Cumberland. ... 600 

Alabama 600 

Susquehanna . . . 500 

Potomac 500 

James 500 

Connecticut .... 450 

Delaware 400 

Hudson 350 

Kenebec 300 

Thames 233 



USEFUL INFORMATION. 



89 



Number of Miles by Water from New York to 



Amsterdam . . . 3510 
Bermudas .... 660 

Bombay 11574 

Boston 310 

Buenos A}-res . . 7110 

Calcutta 12425 

Canton 13900 

Cape Horn .... 8115 
Cape of Good Hope 6830 
Charleston .... 750 
Columbia River . 15965 
Constantinople. . 5140 

Dublin 3225 

Gibraltar 3300 

Halifax 612 

Hamburg .... 3775 

Havana 1420 

Havre 3210 



Kingston. .... 1640 

Lima 11310 

Liverpool .... 3210 

London 3375 

Madras 11850 

Naples 4330 

New Orleans . . . 2045 

Panama 2358 

Pekin 15325 

Philadelphia ... 240 

Quebec 1400 

Rio Janeiro . . . 3840 

Round the Globe 25000 

Sandwich Island . 15300 

San Francisco . . 5858 

St. Petersburg . . 4420 

Valparaiso .... 9750 

Washington ... 400 



Years of Age which various Animals attain. 



Whale 1000 

Elephant 400 

Swan 300 

Tortoise 100 

Eagle 100 

Raven 100 

Camel 100 

Lion 70 

Porpoise 30 

Horse 25 to 30 



Cow . . 
Bear . . 
Deer . . 
Pigs . . 
Cat . . 
Fox . . 
Dog . . 
Sheep . 
Rabbit 
Squirrel 



20 
20 
20 
20 
15 
15 
20 
10 
7 
8 



90 



NATIONAL ELECTRIC FURNACE, 







91 



Boilers of Yarious Types. 



The National Electric Furnace is equally good for 
all constructed t3'pes of boilers. The construction 
of boilers has but very little effect on combustion. 
All that is required in a furnace is, that it must be 
so arranged, that the combustibles, heat, etc., are 
applied to all the heating surface to do the most 
work. In all furnaces, when fire is built upon the 
grate, it is necessary with natural draught to mix 
the air with the gases as close to the fire as possible, 
in order that the mixture may have sufficient heat 
to allow of burning, but, if the gases are allowed to 
escape or disengage and the disengaged carbon is 
cooled below the temperature of ignition, before 
coming into contact with oxygen, it constitutes, 
while floating in gas, smoke. The chilling of the 
gaseous hydro-carbons, which are driven off from 
the solid pieces of coal by the heat developed, maj r 
take place in two ways : either by finding too much 
cold air in the furnace, or by coming into contact 
with a cold body, as the iron of the boiler, the tem- 
perature of which at 75 lbs. pressure steam is 320 ° 
Fahr. ; hence, the heated plates of the boiler, or the 
iron water tubes are below 400 ° Fahr. Thus it will 
be seen that the combustion takes place at the seat 
of fire, where the carbon of the coals, and the 
oxygen of the air have combined. 

The arrangement in the National Electric Furnace 
can be mechanically regulated, so that the flames, 
heat, etc., be of a greater intensity or higher tem- 
perature, and denser or more compressed in the hot 
air space, enough for maintaining a pressure in the 
furnace which should a little more than balance the 
suction of the mixing apparatus and the ascending 
unconsumed and incombustible air in the chimney. 



92 




We will hereinafter give an illustration of a few 
different types of boilers. 

There are manj^ varieties of boilers in all shapes 
and forms ; however, our aim is not to discuss any 
particular type, but to illustrate them to the reader. 
Of the many varieties of the water-tube t} r pe we 
select as an example one from the circular of the 
Babcock & Wilcox Co. The boiler consists of in- 
clined sets of tubes connected at each end by steel 



93 



BABCOCK & WILCOX BOILER. 




Vertical Section. 



castings into which the tubes are expanded ; the 
front and upper ends are connected into a lon- 
gitudinal drum. The rear ends are connected bj T 
inclined pipes to the same drum, while at the bot- 
tom, there is a mud drum of cast iron. There are 
hand holes opposite each end of each tube and man 
heads on the steam and mud drums. The hand holes 
plates are milled to metal contact with the connec- 
tions and the whole section is hung from overhead 



94 



ROOT'S NEW SAFETY BOILER. 




95 



by bolts carried on cross beams resting on the walls. 
The heating surface of the water tubes are all ex- 
posed (or laying bare). The products of combus- 
tion are carried three times across the tubes by 
means of deflectors and those from all the different 
batteries are carried through the pipes of an "econ- 
omizer,", or feed-heater, on their way to the stack. 
In Heine's boiler the connections at the front and 
back ends of the tubes are flat-stayed wrought iron 
plates, the stay bolts are made hollow and plugged ; 
by taking out the plugs the outside of the water 
tubes may be cleaned. There are hand holes and 
plates opposite each end of each tube. The in- 
clination of the tubes is not so great as in the other 
boiler. The product of combustion is carried back- 
wards and forwards between and over the water 
tubes by means of having two layers of fire-brick 
tiles covered over the tubes about three-fourth the 
length. 

Rootfs New Safety Boiler. 

In this view a general arrangement of grate and 
heating surface and front of a 100 H. P. Boiler is 
shown. The feed water entering the mud drum 
at the rear and lower end of tubes is distributed 
through the heaters and thence passes through all 
the 4 inch tubes, forward and upward, until it enters 
the 14 inch tubes at the front end. In the 14 inch 
tubes the steam is separated from the water and 
thoroughly dried while passing along to the cross 
steam drum at the rear, while the water flows 
through the clown takes and re-enters the tubes 
thus completing the circulation. The front ends 
of the tubes rest upon the heavy bearing beam at- 
tached to the front, while the rear and lower ends 
of the tubes rest on the cross mud drum. 



96 



HAEEISON BOILEE 




This arrangement permits the tubes lying in a 
staggered position, which insures a thorough mixture 
of the products of combustion, as well as absorption 
of heat. The flame passes at right angles across 
the "front end of the 4 inch tubes around the 14 inch 



97 



tubes, thence across the lower end of the 4 inch 
tubes and out through the smoke flue of the chim- 
ney. In case of accident to a tube, all that is nec- 
essary to remove it, is to take off two heads at the 
rear and the corresponding bends at the front, re- 
move the lock plate at the rear, then push the pair 
of tubes, containing the injured one to the front 
and thus out. 



Harrison Boiler. 

The most prominent among all them being the 
Harrison, which is made of cast iron globes united 
in straight lines by nicks, flanges and bolts. Each 
line of globes is thus a straight tube with alternate 
enlargements and contractions, and the boiler is 
subject to the incidentals of all the others of the 
tubulous class. The joints are, of course, much 
more numerous than with wrought-iron tubes, but 
they are claimed to be easier to make and to remain 
in better order. A great number of these boilers 
have been in satisfactory use in the eastern part of 
the United States and elsewhere. 

From a Circular. 



The Aetna Grate. 

The Aetna Grate is a practicable and thoroughly 
successful shaking Grate Bar, simple in construc- 
tion, positive and effectual in its operations easily 
worked (being operated in sections in wide fur- 
naces)., gives over 60 per cent, air space. Very 
durable, interchangeable, and can be put in any 
furnace without delay or change of any kind. 



98 




Description. 

Upon the ordinary bearing bars are laid two or 
more, (according to width of furnace) stationary- 
bars, suspended between these in openings near 
either end, are placed two rockers, which swing 
freely like a scale bearing upon pivot edges ; 
upon these rockers are placed the moving bars. 
When at rest they present the same level appear- 



99 



ance as the ordinary grate. Attached to the front 
rocker is an extension socket, reaching almost to 
the ash-pit door ; a lever put in this socket and 
worked imparts to the bars at the same instant a 
vertical and horizontal movement. By this action 
the under surface of the fire is thoroughly cleaned 
and opened. This condition can be maintained 
continuously with one or two moves of the lever, 
which is easily operated with one hand.. 

Grates. 

For small furnaces the grates are usually rigid 
bars ; and the fire is cleaned first by running a 
poker between them. In larger furnaces the grates 
are made to shake or rock, although the former is 
preferable. 

What is the difference between a shaker and a 
rocker grate ? The shaker has merely a horizontal 
movement to and fro, while the rocker turns on a 
pivot and has a vertical motion. Why is a shaker 
preferable? Because, an anthracite coal-fire beds 
down and becomes very compact, and is not seri- 
ously disturbed by shaking ; whereas rocking lifts 
the coals from each other and it takes some time for 
them to readjust themselves and burn as before. 

Eng. Catm. 

Priming in Steamboiler. 

What is priming? 

Priming is a violent agitation of the water within 
the boiler, in consequence of which a large quantity 
of water passes off with the steam in the shape of 
froth or spray. Such a result is injurious, both as 
regards the efficacy of the engine and the safety 



100 

of the engine and boiler ; for the large volume of 
hot water carried over by the steam in condensing- 
engines impairs the vacuum, and throws a great 
load on the air-pump, which diminishes the speed 
and available power of the engine ; and the ex- 
istance of water within the C}^linder, unless there 
be safety valves upon the cylinder to permit its es- 
cape, will very probably cause some part of the 
machinery to break, by suddenly arresting the mo- 
tion of the piston when it meets the surface of the 
water, — the slide valve being closed to the con- 
denser before the termination of the stroke in all 
engines with lap upon the valve, so that the water 
within the cylinder is prevented from escaping in 
that direction if the slide valve be of the kind which 
will not leave its face. At the same time the boiler 
is emptied of its water too rapidly for the feed 
pump to be able to maintain the supply, and the 
tubes are in danger of being burnt from a deficiency 
of water above them. 

What are the causes of priming? 
The causes of priming are an insufficient amount 
of steam room. 

What is the proper remedy for priming? 
When a boiler primes, the engineer generally 
closes the throttle valve, partially turns off the in- 
jection water, if a condensing engine operating by 
jet, and opens the furnace doors, whereby the 
generation of steam is checked, and a less violent 
ebullition in the boiler suffices. Where the priming 
arises from an insufficient amount of steam room, 
it may be mitigated by putting a higher pressure 
upon the boiler and working more expansively, or 
by interposition of a Separator, between the boiler 
and the steam chest. 



101 



Dry Steam Separator. 



INLET 



The Separator consists of a 
vertical cylinder having an in- 
ternal central pipe extending 
from the top downward, about 
one-half its height, which forms 
the outlet pipe. The steam 
enters tangentially to the an- 
nular space between the inner 
and outer pipe at the side near 
the top of the apparatus. The 
speed of the incoming current 
produces centrifugal action, 
causing the steam to pass in a 
spiral line around the inter- 
nal pipe down to its lower 
end where it abruptly changes 
its direction upAvard, passing 
through it and out at the top to 
the point where the steam is to 
be used. The entrained water 
thus separated by the centrif- 
ugal force is thrown to the out- 
side of the downward current 
and falls into the collecting 
chamber below, from whence 
it can be blown off by hand or 
automatically drawn by a pump 
or trap and" returned to the 
boiler without loss of temper- 
ature. 

The importance of dry steam 
cannot be overrated for heat- 
ing or power purposes. All 
steam contains entrained wa- 
ter, either from priming of boi- 
lers or condensation of pipes. 

The Stratton Separator tak- 
ing advantage of the rapidity 
of the steam current, produces 
centrifugal action, separates 
all the entrained water and de- 
livers the steam dry, insuring 
greater efficiency for radiating 
surfaces, increased economy 
for steam engines, overcomes 
all danger from water in steam 
cylinders, and reduces wear 
and tear of pistons, rods and 

Sacking, and when, placed be- 
ers of compound engines in- 
creases their economy and efficiency. 




102 



Albany Steam Trap. 




General View. 

The operation of the trap in connection with the 
filter and boiler will be : The water from the purifier 
having on it the boiler pressure, will flow in through 
the inlet pipe and check valve, entering at first the 
annular chamber exterior to the bucket, after this 
annular space exterior to the bucket has been filled, 
the water will flow over its upper edge and com- 
mence to fill it and will also fill the tank through the 



103 



Cross Section through Syphon and Bucket. 




pipe leading from the bottom of the bucket. After 
sufficient water has entered the bucket to overcome 
its buoyancy, it will suddenly sink and at the same 
time open the equalizing valve, admitting steam 
from the boiler in a few seconds, the pressure 
having become equalized, the water contained in 
the bucket will begin to pass out through the syphon 
pipe into the boiler. After the bucket has been so 
far emptied as to uncover the lower end of the ver- 
tical pipe leading into the upper side of the tank, 
8 



104 




Cross Section through Receiver 



as shown in Fig. 2. steam will pass up through this 
pipe and equalize the pressure in the tank causing 
the containing water to flow into the annular space 
through the check valve shown on lower left side 
of Fig. 2. and thereby float the bucket upwards, 
closing the equalizing steam valve, and in a few 
seconds the pressure in the trap will become re- 
duced from condensation, and again the water will 
be forced from the purifier into it as before de- 
scribed, and the trap will continue to repeat its 
operations. The trap should be set at least three 
feet above water line in boiler. 



105 



L; & X. Automatic Water Gauge. 

The L. axd N. Automatic 
Water Guage, as shown in 
this Cut, is simple in con- 
struction and effective in its 
workings. All the selfacting 
parts are under the control of 
the engineer or fireman, with 
or without pressure in the 
p^r-v — y-.j boiler. The principle is a 

I "~ . -> \ Kj] cylinder and piston. The 

-^-^ end of piston rod projecting 

through the stuffing box with 
handles attached. On the pis- 
ton rod or (self-acting stems) 
are two valve seats; one in 
front of piston which closes 
and stopsthe flow of water and 
steam when a glass breaks, 
the other in the rear of pis- 
ton, that keeps steam or water 
from escaping out through 
stuffing box when it is work- 
ing under pressure. The stuff- 
ing box is only required to 
prevent steam or water escap- 
ing when a glass breaks as 
the rear valve then leaves its 
seat, the front valve closing. 
All the seats can be ground 
in while working under any 
pressure. Working on a boiler 
carrying, say, 60 pounds of 
steam, the self-acting valves 
are held open by about 15 
pounds of pressure. When 
a glass breaks the whole force of steam acts on the piston 
and closes the valve. 

The blow-off being placed between the inlet to boiler 
and end of glass tube, all sediment that may gather in 
the chamber can be thoroughly cleaned away. It is also 
the best indicator of amount of water in the boiler of 




106 



any appliance in use. It has large openings to boiler, 
giving a better circulation through the gauge. 

In case a glass is broken by an accidental blow, or 
bursts through weakness or any other cause {frequent 
occurrences), it will immediately close, thereby prevent- 
ing hot water and steam escaping from the boiler, scald- 
ing bystanders, or those in attendance, shutting down 
the engine, lost time by the stopping of machinery, and 
the necessity often of expensive repairs. After the en- 
gineer has left, and the factory or store closed for the 
night, a glass may break; when this occurs in establish- 
ments where goods are stored of such a nature as may 
be injured by steam, it can readily be seen that a pre- 
ventative device of this kind is of incalculable value, for 
its reliability is certain, and can be depended on day or 
night, in the presence or absence of the person in charge. 



What is Conduction of Heat? 

It is the communication of heat from one body 
to another. In combustion in a furnace for evapo- 
rating water into steam, the heat of the fire pene- 
trates through the boiler plates into the water, and 
drives its atoms apart, expands it ; the water absorbs 
the heat from the fire, thus accomplishing the vapo- 
risation. The latent heat of steam is usually reckoned 
at about 1.000 degrees. The boiling point of water 
being 212 degrees, is 180 degrees above the freezing 
point of water — the freezing point being 32 degrees ; 
so that it requires 1.180 times as much heat to raise 
a pound of water into steam. It is found that the 
most perfect modern engines, when examined, do 
not convert more than about one tenth of the heat 
into power, the rest going off as waste steam. 

In the k 'National Electric Furnace," an arrange- 
ment is presented to the public, wherein the waste 
steam is regenerated and utilized, (as already has 
been stated), by mixing it with the combustible 
gases, and returning it into the fuel, etc. 



107 



Atmospheric Pressure.— Pump. 



How high will atmospheric pressure raise water in the 
bore of a pump'} 

It will raise water to an elevation of thirty feet 
above its level. 

Why will it raise water to an elevation of thirty feet 1 } 
Because a column of water thirtj^ feet high nearly 
balances the weight of a column of air of equal sur- 
face, extending to the whole height of the atmos- 
phere. When, therefore, water is elevated to the 
height of thirty feet, the power of the pump is en- 
feebled, as the air and the water balance each other. 

How is water raised to a greater elevation when it is 
required 1 } 

By mechanical contrivances, by which the water 
is forced to a greater elevation. 



THE SUN. 
What is the distance of the sun from the earth} 
Ninety five millions of miles. 

What is the constitution of the sun} 
It is a spherical body, 1,384,472 times larger 
than the earth. 

From what does the luminosity of the sun arise} 
From a luminous atmosphere, or, as M. Arago 
named it, photosphere, which completely surrounds 
the body of the sun, and which is probably burning 
with great intensity. 



Nearly all Solids become luminous at 800 de- 
grees of heat F. 



108 



What is Water? 



Water is the offspring of two gases, Irydrogen and 
oxygen. If eight pounds of hydrogen and one 
pound of oxygen are mixed and ignited by a flame, 
they combine with a violent explosion and form 
nine pounds of limpid water. If this water is now 
sufficiently heated, e. g. by passing it slowly through 
a red hot tube, it quietly separates into its original 
gases — namely eight pounds of oxj-gen and one of 
hydrogen. Should we deal with these gases by 
volumes, instead of pounds, then three cubic feet 
of the combined gases, of which two are hydrogen 
and one oxygen, if mixed and exploded form water, 
but the water produced only occupies the two thou- 
sand six hundredth part of the space filled by the 
combined gases prior to the explosion. 



Why is the Sea salty? 

Because salt is a mineral which prevails largely 
in the earth, and which, being very soluble in water, 
is taken up by the ocean, lakes and rivers, also, 
even those that are considered fresh, hold in solu- 
tion some degree of saline matters, which they con- 
tribute to the ocean. — As, in the evaporations from 
the sea, the salt remains in it, while the vapours fall 
as rain, and again wash the earth and carry some 
of its mineral properties to the ocean, the greater 
saltness of the sea, as compared with rivers, is 
accounted for. By some persons the opinion is 
entertained that the sea has been gradually getting 
saltier ever since the creation of the world. This, 
they sa}% arises from the evaporation of water free 
from salt, and the return of the water to the sea, 
taking with it salt from the land. 



109 

What is the Depth of the Sea? 

The extreme depth has not, probably, been as- 
certained. But Sir James Ross took soundings 
about 900 miles west of St. Helena, whence he 
found the sea to be nearly six miles in depth. Now 
if we take the height of the highest mountain to be 
five miles, the distance from that extreme rise of 
the earth, to the known depth of the sea, will be no 
less than eleven miles. 

What Proportion of the Earth's Surface is 
covered with Water? 

There are about one hundred and forty seven 
millions of square miles of water, to forty-nine and 
a half millions of square miles of land. 

How do the Waters of the Ocean become heated? 

Chiefly by convection. Nearly all the heat which 
the sun sheds upon the ocean is born away from its 
surface by evaporation, or is radiated back into the 
atmosphere. But the ocean gathers its heat by 
convection from the earth. It girdles the shores 
of tropical lands where, being warmed to a high 
degree of temperature, it sets across the ocean from 
the Gulf of Mexico, and exercises an important 
influence upon the temperature of our latitude. 



The Air, the Atmosphere we Breathe, is com- 
posed of four parts of nitrogen gas and one part of 
oxygen. For example, if we mix four gallons of 
nitrogen and one gallon of oxygen, we have five (5) 
gallons of air. It is the oxygen that supports life ; 
the nitrogen is simply a diluent or spreader. 



110 



The Coal Industry. 



The total product of bituminous coal in the United 
States for the census year closing June, 1880, 
amounted to 40,311,450 tons, of 2,000 pounds to 
the ton, divided among the States as follows : Ala- 
bama, 322,934 tons; Arkansas, 14,778; Georgia, 
154,684; Illinois, 6,089,614; Indiana, 1,449,496 
Iowa, 1,422,333; Kansas, 763,297; Kentucky 
935,857; Maryland, 2,227,844; Michigan, 100,800 
Missouri, 543,900 ; Nebraska, 200 ; North Carolina 
700; Ohio, 3,922,853; Pennsylvania, 18,004,988 
Tennessee, 494,891; Virginia, 40,520; West Vir- 
ginia, 1,702,570. The number of laborers engaged 
in mining this vast amount of coal was 96,475, and 
the wages paid them were $30,707,059. There are 
only two states that produce anthracite coal, Penn- 
sylvania and Rhode Island. The former produced 
28,640,819 tons, and the latter 6,175 tons during 
the census year. The grand total of coal produced 
was 71,067,567 tons, and the grand total of hands 
employed was 170,585. The census bulletin makes 
comparison with the English production. The pop- 
ulation of England is 25,000,000. The production 
of coal in that country in 1855 was 64,661,401 tons ; 
in 1877, 136,179,968 tons, and in 1880, 146,818,152 
tons. The number of collieries in England in 1880 
was 3,380, and in the United States, 3,264. The 
production of coal in England, in an area about 
the size of Ohio, and with half the population of 
the United States, is double that of this country. 
England is supposed to be about up to its maxi- 
mum, while this country is in the infancy of its coal 
development. There are hardly figures enough to 
compute its capacity in this respect, and its pro- 
duction for generations to come will depend upon 



Ill 



the demand. American manufacturing industries 
depend on coal, and in this respect there can be 
no failure. There are several States in which the 
deposits have been barely touched that are equal 
to the whole of England as coal States. 

Chicago Journal of Commerce. 

The Fuel Use of the City of London. 

There are 8,000,000 of tons of coal, independent 
of other fuel materials, annually consumed in that 
great metropolis. In the area of London alone, no 
less than 200,000 tons of fuel are annually cast into 
the air in the form of smoke. And if we take into 
account the vast operation of nature in evaporation, 
fermentation, and putrefactive decomposition, we 
may be enabled to form a conception of the mighty 
part which that thin air, of which we think so little, 
plays in the grand alchemy of nature. 



"Why does the Chimney smoke when the Fire is 
first Lighted ? — Because the air in the chimney is 
of the same temperature as that of the room, and 
therefore will not ascend. 

Why does the Smoking (into the room) cease, 
after the Fire has been Lighted a little while ? 
Because the air in the chimney being warmed by the 
fire beneath, becomes lighter and ascends rapidly. 

Why does a long Chimney create a greater 
Draught than a short one? — Because the short 
chimney contains less air than the long one ; there 
is, consequently, less difference of weight between 
the warm air of the short chimney and the exter- 
nal air ; it therefore has not so great an ascensive 
power. 



112 

Useful Notes on Specific Heat -for Engineers 
and Firemen. 

The specific heat of any substance is the quantity 
of heat expressed in thermal units which must be 
transferred to a pound of the substance to raise its 
temperature 1° Fahr. 

A thermal unit is the quantit}' of heat required 
to raise the temperature of a pound of water from 
39.1° to 40.1° Fahr. 

The specific heat of different bodies varies 
greatly ; it is therefore necessary to select some 
convenient substance and make its specific heat a 
standard by which. that of other bodies may be 
compared. Water is the most convenient substance 
for this purpose, therefore it has been selected for 
such a standard, and the amount of heat . required 
to raise the temperature of a pound of it 1° Fahr., 
has been fixed upon as the standard by which all 
quantities of heat shall be compared. 

The reason why the temperature from 39.1° to 
•40.1° Fahr. is chosen is because 39.1° is the tem- 
perature of greatest density of water, and its spe- 
cific heat, as well as that of all other substances, is 
different at different temperatures. Thus, it re- 
quires about one-twentieth more heat to raise the 
temperature of a pound of water from 211° to 212° 
than it does to raise it from 39.1° 40.1°. 



Fuels. — All those bodies are called fuels, which 
are capable of combining with the oxygen of the air. 
Such a combination is combustion, and restores the 
heat and light that had originally been taken from 
the sun. 

The highest Heat of a common wood fire is 
estimated at 1140° Fahr. 



113 



Open Heaters, Grease in Boilers. 



Is there any objection where the modern -prepara- 
tions of petroleum are used for Cylinder oils ? — The 
objection is not as great as when animal oils are used. 
Still, we find more or less difficulty. The deposit 
which accumulates is of a tenacious, waxy character, 
and is more frequently found adhering to the sides 
of the boiler near the water line and around the 
upper tubes. We are a little troubled to account for 
this, but are of the opinion that it is the paraffine in 
the oil. It should be borne in mind that a large 
proportion of the oil used in the c}dinder is thrown 
out in the exhaust. We will suppose that one pint 
of oil is used in a cylinder each day. If the exhaust 
is returned to the boiler there will have been carried 
into it in one month not much less than three gallons. 
If the water is liable to be muddy or carries any 
considerable quantity of vegetable matter, the oil 
will combine with it more or less, and certainry 
give trouble. Therefore, from a wide experience 
we advise that the exhaust be utilized to heat the 
feed water, without bringing it in contact with it, 
which can not be done unless a pipe or coil heater 
is used. Crude petroleum is very effective in re- 
moving hard scale. But it should be put into the 
boiler when it is comparatively cool, after blowing 
down and cleaning out the boiler. The crude petro- 
leum may be put in when the boiler is being filled ; 
it will rise to the surface of the water, and as the 
water rises in the process of filling, the sides of the 
boiler will be washed by the rising oil on the surface. 
We have been able to remove hard scale in this way 
which could not be removed by any other process. 
Crude petroleum is volatile, and the amount of re- 
siduum which would result from the quantity used 



114 



in a boiler for such purposes would be so small as 
to be harmless. We would not, however, advise 
the indiscriminate use of crude petroleum. If the 
water carries vegetable matter, or is liable to be 
muddy, other purgers will be better. But for a 
hard lime scale we have found crude petroleum very 
effective. It will be observed that the conditions 
under which the oil is used in this case are different 
from those where it is introduced in the exhaust 
from the engine. In the latter case it is introduced 
into the water, which is at a high temperature, and 
may have more or less impurity or scum on the 
surface ; the oil readily combines with this, causing 
the difficulties mentioned above. While in the for- 
mer case the oil is introduced cold into cold water, 
it washes, or "varnishes" the sides of the scale- 
covered boiler, penetrates it, works its way between 
the scale and the iron of the boiler, and detaches it. 
Those who have used petroleum to aid in removing 
a nut from a rusted bolt will understand its oper- 
ation. It eats out or dissolves the rust or oxide 
without injuring the iron. So with hard scale, it 
works down between the iron and the scale, eats 
out or lubricates the film of oxide, and detaches it. 

The Locomotive. 



Why is it dangerous to sit near a Fire during 
an Electric Storm ? — Because the chimney, being 
a tall object, and smoke a good conductor, would 
probably attract the Electricity, and convey it to 
the body of a person sitting near the fire. 

The Speed of an Electric Spark travelling over 
a copper wire, has been ascertained by Wheatstom 
to be 288,000 mi. in a second. 



115 



Earthquakes. 



Earthquakes arise from undulations, heavings, 
and splittings in the earth, caused by the expansion 
of substances under the effects of terrestrial fires. 
Large masses of rock are sometimes hurled from 
mountains, or forced to the surface, from beneath 
the bowels of the earth. One theory explanatory 
of earthquakes is, that our globe, and all other 
planetary bodies, were originally in a state of fire, 
and have since been gradually cooling ; that there 
yet exist within the bowels of the earth the remains 
of its former incandescent state ; that water some- 
times finds its way to the heated mass within ; and 
that this generates steam and gases which, in es- 
caping, rupture and disturb the earth. Another 
theory is, that the earth contains chemical elements ; 
which, under certain circumstances, act upon each 
other and produce fire ; or, under the action of 
water, explode, melt, and fuse — by the intensity 
of heat — the parts of the earth around them. The 
effects of earthquakes, when they are severe, in 
populous districts, are very terrible. In cities, 
churches and buildings of every description are 
thrown down ; thousands of people are crushed to 
death ; fire seizes upon the ruins, and, in some 
instances, whole cities are buried. 

In the year 543, a great earthquake was felt 
throughout the known world ; in 742, more than 500 
towns were destroyed in Syria, Palestine, and Asia ; 
and the loss of lives was beyond all calculation ; in 
1137, 15,000 people perished in the ruins caused 
by an earthquake in Catania, in Sicily ; 40,000 people 
perished by a similar cause at Naples, in 1456 ; in 
1531, 1500 houses were thrown down at Lisbon, 
and 30,000 people perished ; in 1693, another oc- 



116 



curred in Sicily, and destroyed Catania and its 
18,000 inhabitants. Altogether, more than 100,000 
lives were lost. In 1731, another occurred in China, 
when 100,000 people were swallowed up at Pekin ; 
at the great earthquake in Lisbon 1755, in about 
eight minutes, 50,000 inhabitants were swallowed 
up, and the principal parts of the Chy buried. In 
1743, the town of Guatemala, in Mexico — with all 
its riches, and 8000 families — was swallowed up, 
the spot were it was buried being now a complete 
desert. — Bihli. Rea. Why. 



CONCLUSION. 

Our task has now come to its end. The selec- 
tions and teachings herein set forth, are such as 
we thought worth knowing, and we sincerely hope 
they will enable those, who are entirely unac- 
quainted with the science of combustion, to under- 
stand the same. They are not new, as they come 
before our eyes every day. Many persons may not 
have the means of knowing them, except through 
some such effort as this. Many of the dear readers 
also may not be acquainted or familiar with the 
science of chemistry and with chemical terms. Such 
we would friendly advise to peruse . the material 
offered in this little volume, to read over and over 
again, and we are surely convinced that a more 
perfect understanding of the science of combustion 
will be the result. 

The book also contains, as the reader will have 
perceived, an assortment of miscellaneous valuable 
and useful information, comprising what we thought 
mostly new and interesting. We have tried to avoid 
giving a great number of tables and calculations, 



117 



since we believe that the majority of readers care 
very little for them, and have, therefore, given only 
such as we thought to be of special interest. We 
have collected them with much care and expense 
for the benefit of the reader, certainly not for that 
of the writer, who is quite content with the thought 
of having tried to benefit others. The reader may 
as a return favor, if he finds it valuable enough, let 
his friends know of this little volume's being in 
existence, and so help to bring the information 
therein contained to others. — In compiling this 
little volume, the writer was led by a maxim well 
worthy of imitation. — A worthy quaker wrote thus : 
"I expect to pass through this world but once. 
If, therefore, there be any kindness I can do to 
any fellow being, let me do it now, for I will not 
pass this way again." Were all to act thus, how 
many would be made happy ! 



END. 






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